What’s Vulnerable › Vulnerabilities
CVE-2026-92842: OOB read / info leak in convert.* stream filters when line-break-chars contains NUL
- Severity: medium (CVSS 5.9 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2026-09-25 · updated 2026-10-27
- Weakness: CWE-122
Description
The convert.base64-encode, convert.quoted-printable-encode and convert.quoted-printable-decode stream filters accept a line-break-chars option whose length is tracked separately from the string itself. The filter constructors duplicate the value with pestrdup(), which stops at the first NUL byte, while keeping the original length. When the filter later emits a line break it copies the recorded length out of the truncated allocation, reading past its end and placing adjacent heap bytes into the filter output.
Affected products
- PHP: from 8.2.0 before 8.2.34; from 8.3.0 before 8.3.35; from 8.4.0 before 8.4.26; from 8.5.0 before 8.5.11 — fixed in 8.2.34, 8.3.35, 8.4.26, 8.5.11
- PHP: from 8.2.* before 8.2.34; from 8.3.* before 8.3.35; from 8.4.* before 8.4.26; from 8.5.* before 8.5.11 — fixed in 8.2.34, 8.3.35, 8.4.26, 8.5.11
How to fix
Upgrade to a fixed version: PHP 8.2.34, 8.3.35, 8.4.26, 8.5.11; PHP 8.2.34, 8.3.35, 8.4.26, 8.5.11. Check the vendor advisory for mitigations.
References
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