CVE-2026-31958: Snakeviz · Tornado is vulnerable to DoS due to too many multipart parts
Affects snakevizSource GCVE Database
Not known to be exploited · CVSS 8.7 High : upgrade to 2.2.2_3 soon.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 33% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.2.2_3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 11 Mar 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 29 Oct 2026.
What to do
Upgrade snakeviz to 2.2.2_3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewsnakevizpkg:brew/snakevizOther 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
Upgrade Snakeviz to version 2.2.2_3 or later, which includes the fix. Tornado 6.5.5 and later enforce limits on multipart request size and complexity by default and allow disabling multipart parsing if not needed. Applying the official patch eliminates the vulnerability. No additional mitigation is required if the patch is applied.
Description
Tornado versions prior to 6.5.5 have a denial-of-service vulnerability due to unbounded parsing of multipart/form-data requests with many parts. The parsing occurs synchronously on the main thread, allowing an attacker to exhaust resources by sending requests with excessive multipart parts. Tornado 6.5.5 and later introduce configurable limits on multipart body size and complexity, including a default limit of 100 parts per request, and allow disabling multipart parsing if not needed. The vulnerability affects Snakeviz versions >=2.2.0 and <2.2.2_3, which use Tornado. A fix is available in version 2.2.2_3.
References
- github.com/tornadoweb/tornado/security/advisories/GHSA-qjxf-f2mg-c6mc (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-31958 (opens in a new tab)
- github.com/tornadoweb/tornado/commit/119a195e290c43ad2d63a2cf012c29d43d6ed839 (opens in a new tab)
- github.com/pypa/advisory-database/tree/main/vulns/tornado/PYSEC-2026-140.yaml (opens in a new tab)
- github.com/tornadoweb/tornado (opens in a new tab)
- github.com/tornadoweb/tornado/releases/tag/v6.5.5 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2026/04/msg00000.html (opens in a new tab)