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 ?
7.1 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CWE
  • CWE-20 - Improper input validation
Assigner
References
Impacted products
Vendor Product Version
Protocol Buffers Protobuf-php (Pecl) Affected: 0 , < 5.34.0-RC1 (semver)
Affected: 0 , < 4.33.6 (semver)
Create a notification for this product.
Credits
https://github.com/34selen
Show details on NVD website
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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