Vulnerability-Lookup

GHSA-4RGF-7285-CHF8

Vulnerability from github – Published: 2026-08-10 12:31 – Updated: 2026-08-10 12:31

Details

GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it. This can lead to heap memory corruption and potential code execution.

This issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca

Severity

5.3 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-71393"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-190"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T11:17:28Z",
    "severity": "MODERATE"
  },
  "details": "GNU Emacs for Android is vulnerable to an integer overflow in sfnt_read_name_table() in src/sfnt.c. The function computes an allocation size using a 32-bit length value from a TrueType font file without overflow checking. On 32-bit targets, a crafted font causes the calculation to wrap, resulting in an undersized heap allocation. A subsequent read() call writes beyond the buffer, causing a heap buffer overflow. An attacker can deliver a malicious font file via email, EWW (Emacs Web Wowser), or documents with custom faces, causing Emacs to load it.\u00a0This can lead to heap memory corruption and potential code execution.\n\n\n\n\nThis issue was fixed in commit d51a4722316efe0960994d371e1859099894d1ca",
  "id": "GHSA-4rgf-7285-chf8",
  "modified": "2026-08-10T12:31:51Z",
  "published": "2026-08-10T12:31:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-71393"
    },
    {
      "type": "WEB",
      "url": "https://cert.pl/en/posts/2026/08/CVE-2026-71391"
    },
    {
      "type": "WEB",
      "url": "https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=d51a4722316efe0960994d371e1859099894d1ca"
    },
    {
      "type": "WEB",
      "url": "https://www.gnu.org/savannah-checkouts/gnu/emacs/emacs.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-71393 (GCVE-0-2026-71393)

Vulnerability from cvelistv5 – Published: 2026-08-10 10:22 – Updated: 2026-08-10 17:50 X_Open Source

Title

Heap Buffer Overflow in GNU Emacs for Android

Summary

Severity

5.3 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-190 - Integer Overflow or Wraparound

Assigner

CERT-PL

References

3 references

URL	Tags
https://cert.pl/en/posts/2026/08/CVE-2026-71391	third-party-advisory
https://www.gnu.org/savannah-checkouts/gnu/emacs/…	product
https://git.savannah.gnu.org/cgit/emacs.git/commi…	patch

Impacted products

1 product

Vendor	Product	Version
GNU	Emacs	Affected: 0 , ≤ 30.2 (custom)

Credits

Michał Majchrowicz (AFINE Team) Marcin Wyczechowski (AFINE Team)

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JSON

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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.

Action not permitted

GHSA-4RGF-7285-CHF8

CVE-2026-71393 (GCVE-0-2026-71393)

Tags

Sightings

Nomenclature