CVE-2026-92391: curl · A deeply nested multipart MIME structure constructed via the public API causes a stack overflow in
Affects curlSource GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in 7.58.0-2ubuntu3.24+esm15 : patch curl soon.
Data as of 3 Nov 2026, 23:49 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 7.5 |
|---|
- Patch
- Available – fixed in 7.58.0-2ubuntu3.24+esm15, 7.68.0-1ubuntu2.25+esm10, 7.81.0-1ubuntu1.30 +3
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 20 Oct 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 3 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10curlpkg:deb/ubuntu/curl?arch=source&distro=stonkingOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTScurlpkg:deb/ubuntu/curl?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTScurlpkg:deb/ubuntu/curl?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 22.04 LTScurlpkg:deb/ubuntu/curl?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Ubuntu Pro 20.04 LTScurlpkg:deb/ubuntu/curl?arch=source&distro=esm-infra/focalOther threats | Affected
| Fixed in
|
Ubuntu Pro 18.04 LTScurlpkg:deb/ubuntu/curl?arch=source&distro=esm-infra/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.
AI-suggested
A patch is available and should be applied. The vulnerability is fixed in Ubuntu package versions 7.58.0-2ubuntu3.24+esm15, 7.68.0-1ubuntu2.25+esm10, 7.81.0-1ubuntu1.30, 8.5.0-2ubuntu10.16, 8.20.0-2ubuntu11.1, and 8.18.0-1ubuntu2.8. Users should upgrade to these or later versions to remediate the issue.
Description
A vulnerability in libcurl allows a stack overflow due to excessive recursion when processing deeply nested multipart MIME structures via the public API. This occurs during normal cleanup operations in the curl_mime_free function, causing the host process to crash. The issue affects multiple Ubuntu package versions of curl and has been assigned CVE-2026-92391 with a high severity rating.
References
- ubuntu.com/security/CVE-2026-92391 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-92391 (opens in a new tab)
- curl.se/docs/CVE-2026-92391.html (opens in a new tab)
- ubuntu.com/security/notices/USN-8927-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8927-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8932-1 (opens in a new tab)