CVE-2026-27171 (GCVE-0-2026-27171)

Vulnerability from cvelistv5 – Published: 2026-02-18 02:36 – Updated: 2026-02-18 13:38
VLAI
Summary
zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition.
Severity
2.9 (Low)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-1284 - Improper Validation of Specified Quantity in Input
Assigner
References
Impacted products
Vendor Product Version
zlib zlib Affected: 0 , < 1.3.2 (semver)
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.