OOB read / info leak in convert.* stream filters when line-break-chars contains NUL
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- Partial Red Hat: 2 fixed, 5 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| PHP Group | PHP | before 8.2.34; before 8.3.35; before 8.4.26; before 8.5.11 | 8.2.34, 8.3.35, 8.4.26, 8.5.11 | Patch available | CNA |
- PHP VendorPHP Group Affected before 8.2.34; before 8.3.35; before 8.4.26; before 8.5.11 Fixed in 8.2.34, 8.3.35, 8.4.26, 8.5.11 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:php:php:*:*:*:*:*:*:*:* | 8.2.0 to before 8.2.34; 8.3.0 to before 8.3.35; 8.4.0 to before 8.4.26; 8.5.0 to before 8.5.11 | Vulnerable | PHP |
- cpe:2.3:a:php:php:*:*:*:*:*:*:*:* Versions 8.2.0 to before 8.2.34; 8.3.0 to before 8.3.35; 8.4.0 to before 8.4.26; 8.5.0 to before 8.5.11 Vulnerable ·PHP
Remediation
- Fix · CNA PHP (PHP Group) Fixed in 8.2.34, 8.3.35, 8.4.26, 8.5.11
Red Hat 2 advisories
- RHSA-2026:87080 Released 2026-10-21 · Red Hat rating Importantphp:7.4 security update
- Red Hat Enterprise Linux AppStream (v. 8) apcu-panel-5.1.18-1.module+el8.10.0+22485+a3539972.noarch::php:7.4, libzip-1.6.1-1.module+el8.10.0+22485+a3539972.aarch64::php:7.4, libzip-1.6.1-1.module+el8.10.0+22485+a3539972.ppc64le::php:7.4 +47
- RHSA-2026:70720 Released 2026-09-23 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images php-8.5.11-2.hum1@aarch64, php-8.5.11-2.hum1@src, php-8.5.11-2.hum1@x86_64 +47
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
PHP 8.2.34, 8.3.35 and 2 more versions
11 records Highest priority Priority HIGH 1 HIGH, 3 MEDIUM, 7 LOW
Other records, highest priority first
- TI-2026-63096 Out-of-bounds read in the HTTP stream wrapper when following a redirect with an empty Location headerPriority HIGH 65
- TI-2026-14392 PHP on Windows: Reserved Device Names Are Not Rejected Before File/Stream I/O which can cause DoSPriority MEDIUM 64
- TI-2025-12959 Integer overflow to buffer overflow in soap HTTP parsingPriority MEDIUM 62
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2026:87080 |
| Red Hat Hardened Images | Fixed | RHSA-2026:70720 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-92842
- 2026-10-21 Fix available: RHSA-2026:87080 · Red Hat
- 2026-10-21 Fix available: Red Hat Enterprise Linux AppStream (v. 8) · Red Hat
References
More PHP Group vulnerabilities
- TI-2024-04260 Argument Injection in PHP-CGI KEVCVSS 3.1CRITICAL 9.8
- TI-2026-78794 PHP remote code execution via stale global state KEVCVSS 4.0CRITICAL 9.2
- TI-2026-78793 Out-of-memory handling flaw in PHP allows remote code execution KEVCVSS 4.0CRITICAL 9.2
- TI-2024-01743 Command injection via array-ish $command parameter of proc_open() CVSS 3.1CRITICAL 9.4
- TI-2022-13555 PDO::quote() may return unquoted string CVSS 3.1CRITICAL 9.1
- TI-2024-10408 Reference counting in php_request_shutdown causes Use-After-Free CVSS 4.0CRITICAL 9.2
Sources
- CVE-2026-92842 · CVE Program
- CVE-2026-92842 · NVD
- FIRST EPSS
- CVE-2026-92842 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences