Microsoft · `http.cookiejar` applies expired `Set-Cookie` to cookie store before policy validation
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 6.3 Medium : upgrade to 3.16.0 when convenient.
Data as of 10 Nov 2026, 12:06 UTC
Thin evidence
One scorer or none| CNA (PSF) | CVSS 4.0 | 6.3 |
|---|
- Patch
- Available – fixed in 3.16.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 9 Nov 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 10 Nov 2026.
What to do
Upgrade CPython to 3.16.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Python Software FoundationCPython | Affected
| Fixed in
|
GitHubCPythonpkg:github/CPythonOther 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
The vulnerability involves the http.cookiejar component applying expired Set-Cookie headers to the cookie store before performing policy validation. This behavior could lead to improper handling of cookies in Microsoft product version 3.0.