CVE-2026-77641
tor before 0.4.9.9 was prone to a NULL write after free when sending a CONFLUX_SWITCH cell fails. The return value of relay_send_command_from_edge() was ignored, so a send failure (which calls circuit_mark_for_close() and removes the leg via cfx_del_leg()) would go undetected, causing the caller to write to the now-freed current leg and resulting in a crash. This is TROVE-2026-017.
- CVSS 3.1
- 8.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H - EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 28% of CVEs (scores of 2026-10-25)
- CWE
- CWE-252
- Published
- Modified
- Record from
- the NVD, synced
Affected
- torproject:tor