Search criteria
1 vulnerability by Protocol Buffers
CVE-2026-6409 (GCVE-0-2026-6409)
Vulnerability from cvelistv5 – Published: 2026-04-16 14:30 – Updated: 2026-04-16 15:24
VLAI
Title
Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input
Summary
A Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured messages—specifically those containing negative varints or deep recursion—can be used to crash the application, impacting service availability.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-20 - Improper input validation
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Protocol Buffers | Protobuf-php (Pecl) |
Affected:
0 , < 5.34.0-RC1
(semver)
Affected: 0 , < 4.33.6 (semver) |
Credits
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