CVE-2026-44603: torproject Tor · Off-by-one Error
Affects torproject TorSource CVE Database V5
Not known to be exploited · CVSS 3.7 Low : upgrade to 0.4.9.7 when convenient.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 27% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.4.9.7
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 7 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade torproject Tor to 0.4.9.7.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| torprojectTor | Affected
| Fixed in
|
AI-suggested
No specific mitigation actions are currently documented.
Description
CVE-2026-44603 is an off-by-one error vulnerability in Tor versions before 0.4.9.7. It involves an out-of-bounds read by one byte triggered by a malformed BEGIN cell. The vulnerability is classified as CWE-193 and has a low severity with a CVSS score of 3.7.
References
- forum.torproject.org/c/news/tor-release-announcement/28 (opens in a new tab)
- openwall.com/lists/oss-security/2026/05/06/8 (opens in a new tab)
- gitlab.torproject.org/tpo/core/tor/-/work_items/41245 (opens in a new tab)
- gitlab.torproject.org/tpo/core/tor/-/commit/1703df3d439c83c2184e259fad1cfa19240f9c89 (opens in a new tab)