curl · When doing TLS related transfers with reused easy or multi handles and altering the CURLSSLOPT_NO_PARTIALCHAIN option
Affects curlSource GCVE Database
Not known to be exploited · CVSS 5.3 Medium · fixed in 8.5.0-2ubuntu10.7 : update curl when convenient.
Data as of 28 Oct 2026, 22:28 UTC
- Patch
- Available – fixed in 8.5.0-2ubuntu10.7, 8.14.1-2ubuntu1.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 6 Jan 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
Upgrade the Ubuntu curl to 8.5.0-2ubuntu10.7 (package) or 8.14.1-2ubuntu1.1 (package).
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10curlpkg:deb/ubuntu/curl?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTScurlpkg:deb/ubuntu/curl?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.
Description
When doing TLS related transfers with reused easy or multi handles and altering the `CURLSSLOPT_NO_PARTIALCHAIN` option, libcurl could accidentally reuse a CA store cached in memory for which the partial chain option was reversed. Contrary to the user's wishes and expectations. This could make libcurl find and accept a trust chain that it otherwise would not.