Vulnerability-Lookup

GHSA-PW9P-JVRM-F7RM

Vulnerability from github – Published: 2026-06-26 20:55 – Updated: 2026-06-26 20:55

Summary

PHP Standard Library: HTTP/2 server-side missing content-length validation enables request smuggling

Details

Impact

Psl\H2\ServerConnection does not validate that the total bytes received in DATA frames match the content-length header declared in the HEADERS frame, in violation of RFC 9113 §8.1.1.

A malicious client can: - Send more DATA bytes than declared, smuggling additional content past application-level size limits. - Send fewer DATA bytes than declared and close the stream early, causing applications that trust the declared length to behave incorrectly.

The vulnerability is only reachable for consumers using Psl\H2\ServerConnection directly to accept untrusted client traffic. The high-level Psl\HTTP\Server is in active development and was not yet released at the time of this advisory; consumers of documented high-level PSL APIs are not affected.

Patches

Fixed in 6.1.2 and 6.2.1.

Parses and validates the content-length header on incoming HEADERS (server-side only — clients do not enforce this per RFC 9110 §9.3.2).
Tracks cumulative DATA frame payload length per stream.
Throws StreamException on mismatch or overflow.

Regression tests landed in #781, 9 of the new tests fail against the pre-fix code, proving the validation boundary is enforced.

Workarounds

None at the protocol layer. Applications using Psl\H2\ServerConnection directly should upgrade.

Resources

RFC 9113 §8.1.1 (HTTP/2 request/response exchange)
RFC 9110 §8.6 (content-length header)
https://github.com/php-standard-library/php-standard-library/releases/tag/6.1.2
https://github.com/php-standard-library/php-standard-library/releases/tag/6.2.1

Severity

7.5 (High)


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

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "php-standard-library/h2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.1.0"
            },
            {
              "fixed": "6.1.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "php-standard-library/h2"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "php-standard-library/php-standard-library"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.1.0"
            },
            {
              "fixed": "6.1.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "php-standard-library/php-standard-library"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-48979"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-26T20:55:55Z",
    "nvd_published_at": "2026-06-17T21:16:23Z",
    "severity": "HIGH"
  },
  "details": "## Impact\n\n`Psl\\H2\\ServerConnection` does not validate that the total bytes received in DATA frames match the `content-length` header declared in the HEADERS frame, in violation of RFC 9113 \u00a78.1.1.\n\nA malicious client can:\n- Send more DATA bytes than declared, smuggling additional content past application-level size limits.\n- Send fewer DATA bytes than declared and close the stream early, causing applications that trust the declared length to behave incorrectly.\n\nThe vulnerability is only reachable for consumers using `Psl\\H2\\ServerConnection` directly to accept untrusted client traffic. The high-level `Psl\\HTTP\\Server` is in active development and was not yet released at the time of this advisory; consumers of documented high-level PSL APIs are not affected.\n\n## Patches\n\nFixed in [6.1.2](https://github.com/php-standard-library/php-standard-library/releases/tag/6.1.2) and [6.2.1](https://github.com/php-standard-library/php-standard-library/releases/tag/6.2.1).\n\n- Parses and validates the `content-length` header on incoming HEADERS (server-side only \u2014 clients do not enforce this per RFC 9110 \u00a79.3.2).\n- Tracks cumulative DATA frame payload length per stream.\n- Throws `StreamException` on mismatch or overflow.\n\nRegression tests landed in [#781](https://github.com/php-standard-library/php-standard-library/pull/781), 9 of the new tests fail against the pre-fix code, proving the validation boundary is enforced.\n\n## Workarounds\n\nNone at the protocol layer. Applications using `Psl\\H2\\ServerConnection` directly should upgrade.\n\n## Resources\n\n- RFC 9113 \u00a78.1.1 (HTTP/2 request/response exchange)\n- RFC 9110 \u00a78.6 (content-length header)\n- https://github.com/php-standard-library/php-standard-library/releases/tag/6.1.2\n- https://github.com/php-standard-library/php-standard-library/releases/tag/6.2.1",
  "id": "GHSA-pw9p-jvrm-f7rm",
  "modified": "2026-06-26T20:55:55Z",
  "published": "2026-06-26T20:55:55Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/php-standard-library/php-standard-library/security/advisories/GHSA-pw9p-jvrm-f7rm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-48979"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/php-standard-library/php-standard-library"
    },
    {
      "type": "WEB",
      "url": "https://github.com/php-standard-library/php-standard-library/releases/tag/6.1.2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/php-standard-library/php-standard-library/releases/tag/6.2.1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "PHP Standard Library: HTTP/2 server-side missing content-length validation enables request smuggling"
}

CVE-2026-48979 (GCVE-0-2026-48979)

Vulnerability from cvelistv5 – Published: 2026-06-17 20:43 – Updated: 2026-06-18 13:11

Title

PHP Standard Library: HTTP/2 server-side missing content-length validation enables request smuggling

Summary

PHP Standard Library (PSL) is set of APIs covering async, collections, networking, I/O, cryptography, terminal UI, etc. In versions 6.1.0, 6.1.1 and 6.2.0, the Psl\H2\ServerConnection does not validate that the total bytes received in DATA frames match the content-length header declared in the HEADERS frame, allowing request smuggling. This is in violation of RFC 9113 §8.1.1. A malicious client is able to send more DATA bytes than declared, smuggling additional content past application-level size limits and send fewer DATA bytes than declared and close the stream early, causing applications that trust the declared length to behave incorrectly. The vulnerability is only reachable for consumers using Psl\H2\ServerConnection directly to accept untrusted client traffic. Consumers of documented high-level PSL APIs are not affected. This issue has been fixed in versions 6.1.2 and 6.2.1.

Severity

7.5 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/php-standard-library/php-stand…	x_refsource_CONFIRM
https://github.com/php-standard-library/php-stand…	x_refsource_MISC
https://github.com/php-standard-library/php-stand…	x_refsource_MISC

Impacted products

2 products

Vendor	Product	Version
php-standard-library	php-standard-library	Affected: >= 6.1.0, < 6.1.2 Affected: >= 6.2.0, < 6.2.1
php-standard-library	php-standard-library/h2	Affected: >= 6.1.0, < 6.1.2 Affected: >= 6.2.0, < 6.2.1

Show details on NVD website

JSON

To clipboard

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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.

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