CVE-2026-123660: vulnerability-lookup · Unthrottled Resource Allocation
Affects vulnerability-lookupSource CVE Database V5
Not known to be exploited · CVSS 5.3 Medium : upgrade to 6.4.1 when convenient.
Data as of 6 Nov 2026, 09:23 UTC
Thin evidence
One scorer or none| CNA (CIRCL) | CVSS 4.0 | 5.3 |
|---|
- Patch
- Available – fixed in 6.4.1
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA: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 5 Nov 2026.
What to do
Upgrade vulnerability-lookup to 6.4.1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| vulnerability-lookupvulnerability-lookup | Affected
| Fixed in
|
AI-suggested
Upgrade vulnerability-lookup to version 6.4.1 or later, which includes fixes that cap format specifier values, limit rendered template size, and restrict template nesting depth. These controls prevent excessive memory allocation and unhandled recursion. Until upgraded, restrict user account creation or webhook notification template editing to trusted users to reduce risk.
Description
CVE-2026-123660 affects vulnerability-lookup versions 5.5.1 up to but not including 6.4.1. A signed-in user can craft webhook notification payload templates that cause excessive memory allocation during string formatting, leading to potential denial of service. The vulnerability arises because format specifiers in placeholders are passed unchecked to Python's string formatting, allowing very large memory allocations. Version 6.4.1 fixes this by capping format specifier numbers, limiting rendered template size, and restricting template nesting depth.