CVE-2026-123096: anacrolix torrent · Unthrottled Resource Allocation
Affects anacrolix torrentSource CVE Database V5
Not known to be exploited · CVSS 7.1 High.
Data as of 5 Nov 2026, 15:47 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 7.1 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 6.5 |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 5 Nov 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
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| anacrolixtorrent | Affected
| Fixed in– |
Gotorrentpkg:golang/torrentOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, users should avoid using untrusted or malicious HTTP trackers in torrent files or magnet links to reduce exposure to this memory exhaustion vulnerability.
Description
CVE-2026-123096 is a memory exhaustion vulnerability in the anacrolix/torrent client up to version 1.61.0. It arises from the tracker/http package where malicious HTTP trackers can send unbounded announce or scrape responses. These responses are buffered without limits by Client.Announce and Client.Scrape, leading to potential process memory exhaustion and client crashes.
References
- github.com/anacrolix/torrent/pull/1143 (opens in a new tab)
- github.com/anacrolix/torrent/commit/92ad51490479bb8b94720f964b1c67e5a1d68faa (opens in a new tab)
- github.com/anacrolix/torrent/blob/v1.61.0/tracker/http/http.go (opens in a new tab)
- github.com/anacrolix/torrent (opens in a new tab)
- vulncheck.com/advisories/anacrolix-torrent-through-1.61.0-memory-exhaustion-via-unbounded-http-tracker-response (opens in a new tab)