CVE-2026-66752: Rust tiny http · tiny-http through 0.12.0 contains an HTTP request smuggling vulnerability that allows remote attackers to desynchronize request framing by sending a
Affects rust-tiny-httpSource GCVE Database
Not known to be exploited · CVSS 5.4 Medium.
Data as of 28 Oct 2026, 05:11 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 28 Jul 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 26.10rust-tiny-httppkg:deb/ubuntu/rust-tiny-http?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSrust-tiny-httppkg:deb/ubuntu/rust-tiny-http?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSrust-tiny-httppkg:deb/ubuntu/rust-tiny-http?arch=source&distro=nobleOther 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 consider deploying additional protections at the proxy or firewall level to detect and block suspicious Transfer-Encoding headers. Monitoring for anomalous HTTP request patterns related to Transfer-Encoding may help mitigate exploitation attempts.
Description
The rust-tiny-http library through version 0.12.0 contains an HTTP request smuggling vulnerability. This flaw allows remote attackers to desynchronize request framing by sending a Transfer-Encoding header with any value, including non-chunked codings. The library improperly applies chunk-decoding and discards Content-Length, leading to discrepancies with front-end proxies that correctly implement Transfer-Encoding parsing. This can enable request smuggling and cause failed body reads that tie up connections and consume worker threads without signaling errors to clients.
References
- nvd.nist.gov/vuln/detail/CVE-2026-66752 (opens in a new tab)
- github.com/theopaid/HTTP-Request-Smuggling-via-Unparsed-Transfer-Encoding-Values-tiny_http-/tree/master (opens in a new tab)
- vulncheck.com/advisories/tiny-http-http-request-smuggling-via-transfer-encoding-handling (opens in a new tab)
- ubuntu.com/security/CVE-2026-66752 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-66752 (opens in a new tab)