CVE-2026-71981 json
Cypht < 2.12.2 PHP Object Injection RCE via back_query Parameter
published 2mo ago modified 3d ago also EUVD-2026-69650
- cvss
- 8.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 62%
- public exploits
- 0
- none known
Summary
Cypht before 2.12.2 contains a PHP object injection vulnerability that allows authenticated attackers to execute arbitrary operating system commands by supplying a crafted PHP object graph in the back_query GET parameter of the logout handler. Attackers can pass a base64-encoded serialized payload through this parameter, which is decoded and passed directly to unserialize() without an allow-list, signature check, or type restriction, enabling gadget-chain exploitation to achieve remote code execution as the web server process.
Patch / fix
- cypht-org cypht 2.12.2
- github.com/cypht-org/cypht@e4aa2f3 commit
- github.com/cypht-org/cypht#2073 pull request
- github.com/cypht-org/cypht/releases/tag/v2.12.2 release
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2mo ago
Exploit prediction
0.97% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- cypht-org cypht
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
References
-
github.com
/cypht-org/cypht/pull/2073
issue-tracking, patch
-
github.com
/cypht-org/cypht/commit/e4aa2f34e33f9328e8c93514cc3966fc3d99925e
patch
-
github.com
/cypht-org/cypht/releases/tag/v2.12.2
release-notes
-
vulncheck.com
/advisories/cypht-php-object-injection-rce-via-back-query-parameter
third-party-advisory
Sources
- CVE List CVE-2026-71981
- NVD CVE-2026-71981
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.