# CVE-2026-92842 — PHP

> As of 2026-09-25, CVE-2026-92842 is a MEDIUM-severity vulnerability in PHP, CVSS v3.1 5.9. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-92842, most recently “Multiple PHP Vulnerabilities Enable Denial of Service, TLS Verification Bypass, and Credential Leakage (CVE-2026-91765, CVE-2026-91768, CVE-2026-6103 and 8 Others) — GovCERT.HK A26-09-40”.

**Last updated:** 2026-09-25

## What is CVE-2026-92842?

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.

The record classifies CVE-2026-92842 under weakness classes [CWE-122](https://cwe.mitre.org/data/definitions/122.html), [CWE-125](https://cwe.mitre.org/data/definitions/125.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 1 day ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 5.9 — MEDIUM (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-09-25

## Is CVE-2026-92842 being exploited?

No public exploitation evidence for CVE-2026-92842 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-09-25. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- **PHP Group**: PHP

## How to fix CVE-2026-92842

No vendor patch reference has been recorded for CVE-2026-92842 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-92842

1 tracked threat in the Threadlinqs corpus references CVE-2026-92842, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple PHP Vulnerabilities Enable Denial of Service, TLS Verification Bypass, and Credential Leakage (CVE-2026-91765, CVE-2026-91768, CVE-2026-6103 and 8 Others) — GovCERT.HK A26-09-40](https://intel.threadlinqs.com/threat/TL-2026-2658) — MEDIUM · 2026-09-25

## Sources

Enriched from CVE.org, NVD. Last verified by Threadlinqs on 2026-09-26. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [github.com — vendor advisory](https://github.com/php/php-src/security/advisories/GHSA-88hq-2827-7pg6)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-92842
Full detection coverage and IOCs for threats exploiting CVE-2026-92842 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp