CVE-2026-77587 (GCVE-0-2026-77587)

Vulnerability from cvelistv5 – Published: 2026-08-20 20:47 – Updated: 2026-08-25 19:09
VLAI
Summary
Tor before 0.4.9.11 is prone to a use-after-free (and potential double free) of a conflux object when a recovery leg revives a conflux set whose last linked leg has already been closed. A malicious exit node could use this to crash a client. This is TROVE-2026-026.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 19:08 UTC
CWE
  • CWE-911 - Improper Update of Reference Count
Assigner
References
Impacted products
Vendor Product Version CPE status
torproject Tor Affected: 0.4.8.1-alpha , < 0.4.9.11 (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.

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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.
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