CVE-2024-1135
No exploitation reported by the sources we read.
- Published2024-04-16
- WeaknessCWE-444
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.
Timeline
dates in UTC- 2024-04-1600:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2024-1135?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2024-1135?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
CISA-ADP · OSV| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| — | all versions | no fix published | CISA-ADP |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 22.0 | < 22.0.0 | 22.0.0 | OSV |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
Red Hat Security Advisory: RHUI 4.11 security, bugfix, and enhancement update
Fix
- Vendor fix Red Hat Product Security RHSA-2025:1335 · 2 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For detailed instructions on how to apply this update, see: https://docs.redhat.com/en/documentation/red_hat_update_infrastructure/4/html/migrating_red_hat_update_infrastructure/assembl…
- Workaround from the vendor Red Hat Product Security RHSA-2025:1335 · 255 productsRed Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Published
- 2024-04-16
- Last Modified
- 2026-06-17
- NVD status
- Deferred
Frequently asked questions
What is CVE-2024-1135?
Is CVE-2024-1135 actively exploited?
What is the CVSS score for CVE-2024-1135?
Running Gunicorn? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
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Go further
- Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.