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CVE-2026-77642 (GCVE-0-2026-77642)

Vulnerability from cvelistv5 – Published: 2026-08-20 21:15 – Updated: 2026-08-27 16:07
VLAI
Summary
tor before 0.4.9.9 was prone to an out-of-bounds write when parsing a consensus or detached signature with unexpected signature digest type. Impact is minor for most Tor roles, but potentially major for directory authorities. This is TROVE-2026-019.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-27 16:03 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
torproject Tor Affected: 0.2.8.2-alpha , < 0.4.9.9 (custom)
    cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*
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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

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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.
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