Vulnerability-Lookup

CVE-2026-88046 (GCVE-0-2026-88046)

Vulnerability from cvelistv5 – Published: 2026-09-10 16:14 – Updated: 2026-09-15 14:47

Title

rclone: source object names can escape the configured root on upload

Summary

rclone is a command-line program to sync files and directories to and from different cloud storage providers. Prior to 1.75.1, rclone core does not reject parent-directory segments in source Object.Remote() values before fs/list, fs/walk, fs/sync, and fs/operations pass those values to destination backends. A flat-keyspace source object store populated with native non-rclone tooling can contain a raw .. key segment, and affected b2, swift, qingstor, oracleobjectstorage, internetarchive, smb, storj, sftp, webdav, ftp, filelu, shade, and sia destinations use path.Join(root, remote) before EncodeDot can neutralize the segment. A copy or upload can therefore escape the configured root into another bucket, share, or path reachable by the victim credential, with sftp and smb potentially reaching other filesystem or share locations under the same login authority. This issue is fixed in version 1.75.1.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-15 14:47 UTC

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/rclone/rclone/security/advisor…	x_refsource_CONFIRM
https://github.com/rclone/rclone/commit/57842c5ee…	x_refsource_MISC
https://github.com/rclone/rclone/releases/tag/v1.75.1	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version	CPE status
rclone	rclone	Affected: < 1.75.1	guessed

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-88046

Vulnerability from fkie_nvd - Published: 2026-09-10 17:17 - Updated: 2026-09-15 15:17

Severity

5.3 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/rclone/rclone/commit/57842c5ee4e1407eda06a414a36510cce2db4252
	security-advisories@github.com	https://github.com/rclone/rclone/releases/tag/v1.75.1
	security-advisories@github.com	https://github.com/rclone/rclone/security/advisories/GHSA-38xv-hf3p-h7mq

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "rclone",
          "vendor": "rclone",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.75.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "rclone is a command-line program to sync files and directories to and from different cloud storage providers. Prior to 1.75.1, rclone core does not reject parent-directory segments in source Object.Remote() values before fs/list, fs/walk, fs/sync, and fs/operations pass those values to destination backends. A flat-keyspace source object store populated with native non-rclone tooling can contain a raw .. key segment, and affected b2, swift, qingstor, oracleobjectstorage, internetarchive, smb, storj, sftp, webdav, ftp, filelu, shade, and sia destinations use path.Join(root, remote) before EncodeDot can neutralize the segment. A copy or upload can therefore escape the configured root into another bucket, share, or path reachable by the victim credential, with sftp and smb potentially reaching other filesystem or share locations under the same login authority. This issue is fixed in version 1.75.1."
    }
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  "lastModified": "2026-09-15T15:17:24.440",
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GHSA-38XV-HF3P-H7MQ

Vulnerability from github – Published: 2026-09-10 22:45 – Updated: 2026-09-10 22:45

Summary

rclone: source object names can escape the configured root on upload

Details

Summary

Multiple backends, when given a specially crafted object to copy, can escape the backend confinement.

Backend	Keep/Close	Per-backend severity
sftp	Medium	Real filesystem escape, fires under default encoding.
smb	Low-Medium	Escapes to a different SMB share the credential can reach.
ftp	Low	Real, leading-`..` overshoot PoC is partly neutralized by encoding; escape bounded to at/below the login base.
webdav	Low	Server-side ACLs are the real boundary.
b2	Low	Same-account sibling bucket crossing on a flat keyspace.
swift	Low	Same, container.
qingstor	Low	Same.
oracleobjectstorage	Low	Same.
internetarchive	Low	IA items are owner-writable only; confined to user's own items.
storj	Low	Can retarget a different bucket in the same access grant.
filelu	Low	Confined to the user's own account.
shade	Low	Confined to the user's own drive.
sia	Low	siad API password already grants full-daemon access.

Root cause

rclone core does not sanitize .. in a source object's Remote() - verified: nothing in fs/march, fs/sync, fs/list, or fs/operations rejects .. segments before the name reaches the destination backend's Put/Update/Mkdir. Confinement is therefore each backend's responsibility, and these backends join root + remote without a check.

This divides into two classes:

Bucket based backends - bucket.Split(path.Join(f.root, rootRelativePath)):
backend/b2/b2.go:404, backend/swift/swift.go:464, backend/qingstor/qingstor.go:198, backend/oracleobjectstorage/oracleobjectstorage.go:245, backend/internetarchive/internetarchive.go:1016, backend/smb/smb.go:885, backend/storj/fs.go:289.
path.Join collapses .. on the standard (ASCII) form before encoding is applied (e.g. FromStandardPath(path.Join(...)) at backend/b2/b2.go:1641), so EncodeDot never gets the chance to neutralize the ...
lib/bucket.Join does not clean paths (keeps .. as a literal key segment); path.Join does. backend/s3, backend/azureblob, backend/googlecloudstorage already use bucket.Join and are therefore not affected.
Path based backends - path.Join(root, remote) onto a real path:
sftp: remotePath = path.Join(f.absRoot, f.opt.Enc.FromStandardPath(remote)) (backend/sftp/sftp.go:2497). Default encoding is encoder.Display (== Standard), and FromStandardPath short-circuits to a pass-through in that mode, so .. survives; f.absRoot is absolute, so path.Join("/home/user/root", "../../../../etc/passwd") -> /etc/passwd.
webdav: filePath at backend/webdav/webdav.go:426-432.
ftp: path.Join(f.root, remote) at ~14 sites (e.g. backend/ftp/ftp.go:1247).
filelu, shade, sia: analogous joins.

Precondition that limits reachability

For any of these to fire, a source must hand rclone a Remote() containing raw ... That is only possible when:

the source is a flat-keyspace object store (not a filesystem - a local/sftp/smb source cannot represent ../../x as one directory entry), and
the offending key was written with native, non-rclone tooling - rclone's own writer applies EncodeDot and rewrites a .. segment to fullwidth ．．, so you cannot create such a key through rclone.

rclone's source-side listing does pass a natively-planted raw .. key through unchanged (verified for b2: remote := file.Name[len(prefix):] after ToStandardPath, backend/b2/b2.go:858,867). The reports never establish this precondition; it is the same omission across every member of the class.

Example attack

# Step 1 - attacker, using NATIVE S3 tooling (NOT rclone) on a source the victim ingests from:
aws s3api put-object --bucket shared-drop --key '../../victim-backups/pwned.txt' --body evil.txt

# Step 2 - victim's ordinary ingest:
rclone copy s3-drop:shared-drop b2:victim-uploads/incoming
# path.Join("victim-uploads/incoming", "../../victim-backups/pwned.txt") = "victim-backups/pwned.txt"
# -> lands in the victim's victim-backups bucket instead of under incoming/

The blast radius is the victim's own account (a bucket/share/path the configured credential already reaches) - integrity misdirection, not a cross-tenant or confidentiality breach. sftp/smb are the exception in reach (server filesystem / other share), still bounded by the login's own permissions.

Precedent

This is the same class as the already-fixed local backend advisory https://github.com/rclone/rclone/security/advisories/GHSA-7p4m-qxvv-g567, which added (*Fs).localPath returning errPathEscapes for names resolving outside the root (backend/local/local.go:819-826). That fix was justified because the destination was the operator's own OS filesystem; the same reasoning extends (at lower severity) to sftp/smb.

Severity

5.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/rclone/rclone"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.75.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-88046"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-10T22:45:36Z",
    "nvd_published_at": "2026-09-10T17:17:08Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nMultiple backends, when given a specially crafted object to copy, can escape the backend confinement.\n\n| Backend | Keep/Close | Per-backend severity |\n|---|---|---|\n| sftp | Medium | Real filesystem escape, fires under default encoding. |\n| smb | Low-Medium | Escapes to a different SMB share the credential can reach. |\n| ftp | Low | Real, leading-`..` overshoot PoC is partly neutralized by encoding; escape bounded to at/below the login base. |\n| webdav | Low | Server-side ACLs are the real boundary. |\n| b2 | Low | Same-account sibling **bucket** crossing on a flat keyspace. |\n| swift | Low | Same, container. |\n| qingstor | Low | Same. |\n| oracleobjectstorage | Low | Same. |\n| internetarchive | Low | IA items are owner-writable only; confined to user\u0027s own items. |\n| storj | Low | Can retarget a different bucket in the same access grant. |\n| filelu | Low | Confined to the user\u0027s own account. |\n| shade | Low | Confined to the user\u0027s own drive. |\n| sia | Low | siad API password already grants full-daemon access. |\n\n## Root cause\n\nrclone core does **not** sanitize `..` in a source object\u0027s `Remote()` - verified: nothing in `fs/march`, `fs/sync`, `fs/list`, or `fs/operations` rejects `..` segments before the name reaches the destination backend\u0027s `Put`/`Update`/`Mkdir`. Confinement is therefore each backend\u0027s responsibility, and these backends join `root + remote` without a check.\n\nThis divides into two classes:\n\n- **Bucket based backends** - `bucket.Split(path.Join(f.root, rootRelativePath))`:\n  - `backend/b2/b2.go:404`, `backend/swift/swift.go:464`, `backend/qingstor/qingstor.go:198`, `backend/oracleobjectstorage/oracleobjectstorage.go:245`, `backend/internetarchive/internetarchive.go:1016`, `backend/smb/smb.go:885`, `backend/storj/fs.go:289`.\n  - `path.Join` collapses `..` on the standard (ASCII) form **before** encoding is applied (e.g. `FromStandardPath(path.Join(...))` at `backend/b2/b2.go:1641`), so `EncodeDot` never gets the chance to neutralize the `..`.\n  - `lib/bucket.Join` does **not** clean paths (keeps `..` as a literal key segment); `path.Join` does. `backend/s3`, `backend/azureblob`, `backend/googlecloudstorage` already use `bucket.Join` and are therefore not affected.\n\n- **Path based backends** - `path.Join(root, remote)` onto a real path:\n  - sftp: `remotePath = path.Join(f.absRoot, f.opt.Enc.FromStandardPath(remote))` (`backend/sftp/sftp.go:2497`). Default encoding is `encoder.Display` (== `Standard`), and `FromStandardPath` short-circuits to a pass-through in that mode, so `..` survives; `f.absRoot` is absolute, so `path.Join(\"/home/user/root\", \"../../../../etc/passwd\")` -\u003e `/etc/passwd`.\n  - webdav: `filePath` at `backend/webdav/webdav.go:426-432`.\n  - ftp: `path.Join(f.root, remote)` at ~14 sites (e.g. `backend/ftp/ftp.go:1247`).\n  - filelu, shade, sia: analogous joins.\n\n### Precondition that limits reachability\n\nFor any of these to fire, a **source** must hand rclone a `Remote()` containing raw `..`. That is only possible when:\n\n1. the source is a **flat-keyspace object store** (not a filesystem - a local/sftp/smb source cannot represent `../../x` as one directory entry), **and**\n2. the offending key was written with **native, non-rclone tooling** - rclone\u0027s own writer applies `EncodeDot` and rewrites a `..` segment to fullwidth `\uff0e\uff0e`, so you cannot create such a key *through rclone*.\n\nrclone\u0027s source-side listing does pass a natively-planted raw `..` key through unchanged (verified for b2: `remote := file.Name[len(prefix):]` after `ToStandardPath`, `backend/b2/b2.go:858,867`). The reports never establish this precondition; it is the same omission across every member of the class.\n\n### Example attack\n\n```bash\n# Step 1 - attacker, using NATIVE S3 tooling (NOT rclone) on a source the victim ingests from:\naws s3api put-object --bucket shared-drop --key \u0027../../victim-backups/pwned.txt\u0027 --body evil.txt\n\n# Step 2 - victim\u0027s ordinary ingest:\nrclone copy s3-drop:shared-drop b2:victim-uploads/incoming\n# path.Join(\"victim-uploads/incoming\", \"../../victim-backups/pwned.txt\") = \"victim-backups/pwned.txt\"\n# -\u003e lands in the victim\u0027s victim-backups bucket instead of under incoming/\n```\n\nThe blast radius is the victim\u0027s **own** account (a bucket/share/path the configured credential already reaches) - integrity misdirection, not a cross-tenant or confidentiality breach. sftp/smb are the exception in *reach* (server filesystem / other share), still bounded by the login\u0027s own permissions.\n\n## Precedent\n\nThis is the same class as the already-fixed local backend advisory [https://github.com/rclone/rclone/security/advisories/GHSA-7p4m-qxvv-g567](GHSA-7p4m-qxvv-g567), which added `(*Fs).localPath` returning `errPathEscapes` for names resolving outside the root (`backend/local/local.go:819-826`). That fix was justified because the destination was the operator\u0027s own OS filesystem; the same reasoning extends (at lower severity) to sftp/smb.",
  "id": "GHSA-38xv-hf3p-h7mq",
  "modified": "2026-09-10T22:45:36Z",
  "published": "2026-09-10T22:45:36Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rclone/rclone/security/advisories/GHSA-38xv-hf3p-h7mq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-88046"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rclone/rclone/commit/57842c5ee4e1407eda06a414a36510cce2db4252"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rclone/rclone"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rclone/rclone/releases/tag/v1.75.1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "rclone: source object names can escape the configured root on upload"
}

ubuntu-cve-2026-88046

Vulnerability from osv_ubuntu

Published

2026-09-11 00:00

Modified

2026-09-14 08:43

Summary

Details

(rclone is a command-line program to sync files and directories to and ...)

Severity

5.3 (Medium)


                    
                      CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-88046	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-88046	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-ncw-rclone-dev",
            "binary_version": "1.36-3ubuntu0.2"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.36-3ubuntu0.2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.36-3ubuntu0.2?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.36-3",
        "1.36-3ubuntu0.1",
        "1.36-3ubuntu0.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.50.2-2ubuntu0.2+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.50.2-2ubuntu0.2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:20.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.50.2-2ubuntu0.2+esm1?arch=source\u0026distro=esm-apps/focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.47.0+ex1-6",
        "1.47.0+ex1-7",
        "1.49.5-2",
        "1.49.5-3",
        "1.50.2-2",
        "1.50.2-2ubuntu0.1",
        "1.50.2-2ubuntu0.2",
        "1.50.2-2ubuntu0.2+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.53.3-4ubuntu1.22.04.5+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.53.3-4ubuntu1.22.04.5+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.53.3-4ubuntu1.22.04.5+esm1?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.53.3-1",
        "1.53.3-2",
        "1.53.3-4",
        "1.53.3-4ubuntu1",
        "1.53.3-4ubuntu1.22.04.1",
        "1.53.3-4ubuntu1.22.04.2",
        "1.53.3-4ubuntu1.22.04.3",
        "1.53.3-4ubuntu1.22.04.3+esm1",
        "1.53.3-4ubuntu1.22.04.4",
        "1.53.3-4ubuntu1.22.04.4+esm1",
        "1.53.3-4ubuntu1.22.04.5",
        "1.53.3-4ubuntu1.22.04.5+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:24.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.60.1+dfsg-3ubuntu0.24.04.6+esm1?arch=source\u0026distro=esm-apps/noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.60.1+dfsg-2build1",
        "1.60.1+dfsg-3",
        "1.60.1+dfsg-3ubuntu0.24.04.1",
        "1.60.1+dfsg-3ubuntu0.24.04.2",
        "1.60.1+dfsg-3ubuntu0.24.04.3",
        "1.60.1+dfsg-3ubuntu0.24.04.4",
        "1.60.1+dfsg-3ubuntu0.24.04.4+esm1",
        "1.60.1+dfsg-3ubuntu0.24.04.5",
        "1.60.1+dfsg-3ubuntu0.24.04.5+esm1",
        "1.60.1+dfsg-3ubuntu0.24.04.6",
        "1.60.1+dfsg-3ubuntu0.24.04.6+esm1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-rclone-rclone-dev",
            "binary_version": "1.60.1+dfsg-4ubuntu3.2+esm1"
          },
          {
            "binary_name": "rclone",
            "binary_version": "1.60.1+dfsg-4ubuntu3.2+esm1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:26.04:LTS",
        "name": "rclone",
        "purl": "pkg:deb/ubuntu/rclone@1.60.1+dfsg-4ubuntu3.2+esm1?arch=source\u0026distro=esm-apps/resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.60.1+dfsg-4ubuntu2",
        "1.60.1+dfsg-4ubuntu3",
        "1.60.1+dfsg-4ubuntu3.1",
        "1.60.1+dfsg-4ubuntu3.1+esm1",
        "1.60.1+dfsg-4ubuntu3.2",
        "1.60.1+dfsg-4ubuntu3.2+esm1"
      ]
    }
  ],
  "aliases": [],
  "details": "(rclone is a command-line program to sync files and directories to and ...)",
  "id": "UBUNTU-CVE-2026-88046",
  "modified": "2026-09-14T08:43:30Z",
  "published": "2026-09-11T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-88046"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-88046"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-88046"
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-88046 (GCVE-0-2026-88046)

FKIE_CVE-2026-88046

GHSA-38XV-HF3P-H7MQ

Summary

Root cause

Precondition that limits reachability

Example attack

Precedent

ubuntu-cve-2026-88046

Vulnerability from osv_ubuntu

Tags

Sightings

Nomenclature