Vulnerability-Lookup

CVE-2026-66753 (GCVE-0-2026-66753)

Vulnerability from cvelistv5 – Published: 2026-07-28 15:46 – Updated: 2026-07-28 19:30 X_Open Source

Title

tiny-http 0.12.0 HTTP Response Splitting via Header Injection

Summary

tiny-http through 0.12.0 contains an HTTP header injection vulnerability that allows attackers to inject carriage return (0x0D) and line feed (0x0A) bytes into HTTP header values on both request and response sides due to insufficient validation in header parsing and serialization. Attackers can exploit this injection primitive to perform response splitting, cache poisoning, session fixation via Set-Cookie injection, security header override, and request smuggling against line-feed-tolerant backends.

Severity

6.3 (Medium)


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

3.7 (Low)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

Assigner

VulnCheck

References

2 references

URL	Tags
https://github.com/theopaid/HTTP-Header-Injection…	technical-descriptionexploit
https://www.vulncheck.com/advisories/tiny-http-ht…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
tiny-http	tiny-http	Affected: 0 , ≤ 0.12.0 (semver)

Date Public

2026-07-26 00:00

Credits

Theodosis Paidakis

Show details on NVD website

JSON

To clipboard

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GHSA-5WM6-G4FR-88X8

Vulnerability from github – Published: 2026-07-28 18:33 – Updated: 2026-07-28 18:33

Details

Severity

3.7 (Low)


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

6.3 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-66753"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-113"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-28T16:20:17Z",
    "severity": "MODERATE"
  },
  "details": "tiny-http through 0.12.0 contains an HTTP header injection vulnerability that allows attackers to inject carriage return (0x0D) and line feed (0x0A) bytes into HTTP header values on both request and response sides due to insufficient validation in header parsing and serialization. Attackers can exploit this injection primitive to perform response splitting, cache poisoning, session fixation via Set-Cookie injection, security header override, and request smuggling against line-feed-tolerant backends.",
  "id": "GHSA-5wm6-g4fr-88x8",
  "modified": "2026-07-28T18:33:03Z",
  "published": "2026-07-28T18:33:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-66753"
    },
    {
      "type": "WEB",
      "url": "https://github.com/theopaid/HTTP-Header-Injection-via-Unvalidated-CR-and-LF-in-Header-Values-tiny_http-/tree/master"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/tiny-http-http-response-splitting-via-header-injection"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/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"
    }
  ]
}

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

CVE-2026-66753 (GCVE-0-2026-66753)

GHSA-5WM6-G4FR-88X8

Tags

Sightings

Nomenclature