Use-After-Free in libphp (CVE-2026-7261)
Summary
Vulnerability in libphp (CVE-2026-7261). Successful exploitation can lead to full system takeover. Mitigation: upgrade to 8.2.31, 8.3.31, 8.4.21, 8.5.6 or later.
Original description
The description as published by the source.
In PHP versions 8.2.* before 8.2.31, 8.3.* before 8.3.31, 8.4.* before 8.4.21, and 8.5.* before 8.5.6, when SoapServer is configured with SOAP_PERSISTENCE_SESSION, the handler object is persisted across requests via session storage. However, in the case SOAP requests results in an error, the persistance is handled incorrectly, resulting in freeing the object while keeping a pointer to it, which may lead to use-after-free. This may lead to memory corruption, information disclosure, or process crashes, with confidentiality, integrity, and availability impact on the vulnerable system.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-7261 has been found in libphp.
Successful exploitation can lead to full system takeover. CVSS score: 9.8/10.
What to do: upgrade libphp to 8.2.31, 8.3.31, 8.4.21, 8.5.6 or later.
If unsure, ask your IT team or search "libphp CVE-2026-7261" on the vendor's site.
CVE-2026-7261 (libphp) — CWE-416 / CVSS v3 9.8
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 8.2.31, 8.3.31, 8.4.21, 8.5.6 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Use-after-free (CWE-416) exists in libphp.
Check the vendor advisory for the affected versions of libphp.
Severity: Critical (CVSS 9.8/10). Successful exploitation can lead to full system takeover.
Update to 8.2.31, 8.3.31, 8.4.21, 8.5.6.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'libphp' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'libphp' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
libphpを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade libphp to 8.2.31, 8.3.31, 8.4.21, 8.5.6ステージング環境で 8.2.31, 8.3.31, 8.4.21, 8.5.6 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-7261 php83 Fixed in: 8.3.31-r0
- Debian DEBIAN-CVE-2026-7261 php7.4 Fixed in: 7.4.33-1+deb11u11
- Ubuntu UBUNTU-CVE-2026-7261 php5
References
- advisory github.com
- web nvd.nist.gov