CVE catalog
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 circu
- Severity
- Medium · CVSS 6.5
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.35% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | tor | sid | 0.4.9.14-1 | fixed |
| Debian | tor | forky | 0.4.9.14-1 | fixed |
| Debian | tor | trixie | 0.4.9.11-0+deb13u1 | fixed |
| Debian | tor | trixie-security | 0.4.9.14-0+deb13u1 | fixed |
| Debian | tor | bookworm | 0.4.9.11-0+deb12u1 | fixed |
| Debian | tor | bookworm-security | 0.4.9.11-0+deb12u1 | fixed |
| Cpe | tor | Not reported | 0.4.9.9 | fixed |
| Ubuntu | tor | pro | 0.4.1.5-1 | vulnerable |
| Ubuntu | tor | pro | 0.4.1.5-1build1 | vulnerable |
| Ubuntu | tor | pro | 0.4.1.6-1 | vulnerable |
| Ubuntu | tor | pro | 0.4.2.5-1 | vulnerable |
| Ubuntu | tor | pro | 0.4.2.6-1 | vulnerable |
| Ubuntu | tor | pro | 0.4.2.7-1 | vulnerable |
| Ubuntu | tor | pro | 0.4.2.7-1ubuntu0.1~esm1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.5.9-1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.6.8-1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.6.8-1build1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.6.9-1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.6.10-1 | vulnerable |
| Ubuntu | tor | 22.04 | 0.4.9.11-0ubuntu0.22.04.1 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.4-2 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.7-1 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.9-1 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.10-1 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.10-1build1 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.8.10-1build2 | vulnerable |
| Ubuntu | tor | 24.04 | 0.4.9.11-0ubuntu0.24.04.1 | vulnerable |
| Ubuntu | tor | 26.04 | 0.4.8.16-1 | vulnerable |
| Ubuntu | tor | 26.04 | 0.4.8.21-1 | vulnerable |
| Ubuntu | tor | 26.04 | 0.4.8.22-1 | vulnerable |
| Ubuntu | tor | 26.04 | 0.4.9.6-1 | vulnerable |
| Ubuntu | tor | 26.04 | 0.4.9.11-0ubuntu0.26.04.1 | vulnerable |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | tor | source | sid | 0.4.9.9-1 | not yet assigned | Not reported | Not reported |
| Debian | tor | source | forky | 0.4.9.9-1 | not yet assigned | Not reported | Not reported |
| Debian | tor | source | trixie | 0.4.9.11-0+deb13u1 | not yet assigned | Not reported | Not reported |
| Debian | tor | source | bookworm | 0.4.9.9-1 | not yet assigned | Not reported | Not reported |
| Cpe | tor | cpe | Not reported | 0.4.9.9 | Not reported | NVD-CVE-2026-77641 | Not reported |
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [tor]Affected
Details (6)
0.4.9.11-0+deb12u1· amd64 · bookwormFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· arm64 · bookwormFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.8.14-1~bpo12+1· amd64 · bookworm-backportsAffected · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.8.14-1~bpo12+1· arm64 · bookworm-backportsAffected · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· amd64 · bookworm-securityFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· arm64 · bookworm-securityFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
- [tor-geoipdb]Affected
Source package: [tor]
Details (6)
0.4.9.11-0+deb12u1· all · bookwormFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· all · bookwormFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.8.14-1~bpo12+1· all · bookworm-backportsAffected · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.8.14-1~bpo12+1· all · bookworm-backportsAffected · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· all · bookworm-securityFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
0.4.9.11-0+deb12u1· all · bookworm-securityFixed · Fixed:
0.4.9.9-1nvd · tor · debian · bookworm; nvd · tor · debian · 12
[Debian 13 (Trixie)]
- [tor]Fixed
Details (10)
0.4.9.11-0+deb13u1· amd64 · trixieFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· arm64 · trixieFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-1~bpo13+1· amd64 · trixie-backportsFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-1~bpo13+1· arm64 · trixie-backportsFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· amd64 · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· arm64 · trixie-securityFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.12-0+deb13u1· amd64 · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.12-0+deb13u2· amd64 · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.13-0+deb13u1· amd64 · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.14-0+deb13u1· amd64 · trixie-securityFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
- [tor-geoipdb]Fixed
Source package: [tor]
Details (10)
0.4.9.11-0+deb13u1· all · trixieFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· all · trixieFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-1~bpo13+1· all · trixie-backportsFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-1~bpo13+1· all · trixie-backportsFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· all · trixie-securityFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.11-0+deb13u1· all · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.12-0+deb13u1· all · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.12-0+deb13u2· all · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.13-0+deb13u1· all · trixie-security · Historical versionFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
0.4.9.14-0+deb13u1· all · trixie-securityFixed · Fixed:
0.4.9.11-0+deb13u1nvd · tor · debian · 13
Observed:
References
- [https://nvd.nist.gov/vuln/detail/CVE-2026-77641]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-77641]
- [https://osv.dev/vulnerability/UBUNTU-CVE-2026-77641]
- [https://security-tracker.debian.org/tracker/CVE-2026-77641]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2959.json]
[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database]