Microsoft · undici vulnerable to cross-origin credential disclosure via array-of-tuples headers bypassing redirect stripping
Affects MicrosoftSource GCVE Database
Not known to be exploited · CVSS 5.9 Medium : upgrade to 8.12.4 or 7.30.2 when convenient.
Data as of 11 Nov 2026, 09:36 UTC
Thin evidence
One scorer or none| CNA (openjs) | CVSS 3.1 | 5.9 |
|---|
- Patch
- Available – fixed in 8.12.4, 7.30.2
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 6 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 undici to 8.12.4 or 7.30.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| undiciundici | Affected
| Fixed in
|
| undiciundici | Affected
| Fixed in
|
npmundicipkg:npm/undiciOther 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
If you cannot patch yet, cautious use of the affected version is advised, especially in environments where cross-origin requests and credential handling are critical.
Description
A vulnerability identified as CVE-2026-120415 affects the undici HTTP client library version 3.0. This flaw allows cross-origin credential disclosure by bypassing redirect stripping through the use of array-of-tuples headers. The issue is categorized under CWE-200, indicating information exposure. No CVSS score or detailed impact metrics are provided.