Vulnerability · RUSTSEC-2026-0446
Request smuggling through malformed chunked request trailers
Published Nov 6, 2026 · RustSec Rust
Last checked Nov 7, 2026. A connected source was read within the last 7 days.
Open the advisory
Exploitation likelihood is not on this record for RUSTSEC-2026-0446. A missing EPSS score is not a low risk. Compare RustSec Rust with the linked advisory before you change production.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- EPSS is missing. A missing score is not a low risk.
Same product and reporting
- RUSTSEC-2026-0455 · Unknown
- RUSTSEC-2026-0447 · Unknown
- RUSTSEC-2026-0443 · Unknown
- RUSTSEC-2026-0445 · Unknown
- RUSTSEC-2026-0448 · Unknown
- Severity
- Unknown—
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- Awaiting synchronization with FIRST
- Remediation
- Not established
- Affected products
- RustSec Rust
The HTTP/1 chunked decoder accepts a bare line feed after the final chunk as the start of a trailer instead of rejecting the malformed request. When an upstream proxy reuses a connection and either pipelines the requests or does not take steps to validate the chunked stream, the decoder can consume the next request's headers as trailer data. It can then parse that request's body as a new request. An attacker can use this difference in request parsing to bypass access controls enforced by a proxy or web application firewall. Upgrade to actix-http 3.20.2 or later.
No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.
How to fix RUSTSEC-2026-0446
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
No version range is stored, so an installed version cannot be checked on this page.
Advisory
Open the rustsec record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
Exploitation likelihood is not on this record for RUSTSEC-2026-0446. A missing EPSS score is not a low risk. Compare RustSec Rust with the linked advisory before you change production.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS is not on this record yet. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Nov 6, 2026 · RustSec Advisory DB
Detected
The HTTP/1 chunked decoder accepts a bare line feed after the final chunk as the start of a trailer instead of rejecting the malformed request. When an upstream proxy reuses a connection and either pipelines the requests or does not take steps to validate the chunked stream, the decoder can consume the next request's headers as trailer data. It can then parse that request's body as a new request.
Sources
- RustSec Advisory DBVendor advisoryRUSTSEC-2026-0446
The HTTP/1 chunked decoder accepts a bare line feed after the final chunk as the start of a trailer instead of rejecting the malformed request. When an upstream proxy reuses a connection and either pipelines the requests or does not take steps to validate the chunked stream, the
crates.io
Freshness
Last verified in this catalog Unknown date. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- RustSec Advisory DBNov 7, 2026