CVE-2026-87724

medium

Tor before 0.4.9.12 interprets the CC_RESPONSE extension even when CC_REQUEST was not sent, which allows remote attackers to cause a denial of service (crash)…

Tor before 0.4.9.12 interprets the CC_RESPONSE extension even when CC_REQUEST was not sent, which allows remote attackers to cause a denial of service (crash) because of corrupted congestion-control state. This is TROVE-2026-032.

CVSS

6.5

6.5 (CVSS v3.1)

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

Severity source: NVD CVSS v3.1 (cve@mitre.org)

Timeline (UTC)

Published: 2026-09-09 02:16

Modified: 2026-09-09 19:17

NVD status: Deferred

Last synced 1 day ago

Verified against the source API 2026-10-27 06:52 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-669

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

https://gitlab.com/torproject/tor/-/commit/10d4b8ffefa7c00aab2b631ed7e7f15e42cd012d cve@mitre.org
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.12/ChangeLog cve@mitre.org

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:52 UTC · record ↗

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