bandit · Improper Cleanup on Thrown Exception Vulnerability
Affects banditSource GCVE Database
Not known to be exploited · CVSS 8.2 High.
Data as of 28 Oct 2026, 22:31 UTC
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10banditpkg:deb/ubuntu/bandit?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSbanditpkg:deb/ubuntu/bandit?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSbanditpkg:deb/ubuntu/bandit?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSbanditpkg:deb/ubuntu/bandit?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSbanditpkg:deb/ubuntu/bandit?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSbanditpkg:deb/ubuntu/bandit?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
Improper Cleanup on Thrown Exception vulnerability in the HTTP/2 handler of mtrudel bandit allows an unauthenticated remote attacker to bypass per-connection resource limits via a single TCP write that carries several frames, one of which raises a stream error. When a frame raises StreamError partway through a chunk, Bandit.HTTP2.Handler.handle_data/3 sends RST_STREAM and continues with the connection state from before the chunk, dropping the rest of it. Streams opened by earlier frames in the chunk keep running their Plug calls, but the stream counts, last_stream_id, the rapid-reset timestamps, the HPACK decoder state and the buffer roll back, so max_concurrent_streams, max_requests and the rapid-reset limiter never see those streams. A client that sends one HEADERS frame more than max_concurrent_streams in each write has the extra refused and the others forgotten: with a limit of 10, five such writes run 50 Plug calls at once. This issue affects bandit: from 1.9.0 before 1.14.0.
References
- ubuntu.com/security/CVE-2026-111103 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-111103 (opens in a new tab)
- cna.erlef.org/cves/cve-2026-111103.html (opens in a new tab)
- github.com/mtrudel/bandit/commit/220b9dfd27f9a21305be2afc75cbe585ddc24e7a (opens in a new tab)
- github.com/mtrudel/bandit/commit/3ad49c80c268891e7cc412e69649115456638e59 (opens in a new tab)
- github.com/mtrudel/bandit/security/advisories/ghsa-2238-pgfc-w82m (opens in a new tab)
- hex.pm/packages/bandit (opens in a new tab)
- github.com (opens in a new tab)
- github.com/mtrudel/bandit (opens in a new tab)
- repo.hex.pm (opens in a new tab)
- github.com/cveproject/cvelistv5/tree/main/cves/2026/111xxx/cve-2026-111103.json (opens in a new tab)
- nvd.nist.gov/vuln/detail/cve-2026-111103 (opens in a new tab)
- osv.dev/vulnerability/eef-cve-2026-111103 (opens in a new tab)