CVE-2026-77641 (GCVE-0-2026-77641)

Vulnerability from cvelistv5 – Published: 2026-08-20 21:09 – Updated: 2026-08-20 21:09
VLAI
Summary
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.
CWE
Impacted products
Vendor Product Version CPE status
torproject Tor Affected: 0.4.8.1-alpha , < 0.4.9.9 (custom)
    cpe:2.3:a:torproject:tor:*:*:*:*:*:*:*:*
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Show details on NVD website

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    "dateReserved": "2026-08-20T21:09:40.882Z",
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    "state": "PUBLISHED"
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  }
}



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