CVE-2026-13311: ljharb shell-quote · Inefficient Algorithmic Complexity
Affects ljharb shell-quoteSource CVE Database V5
Not known to be exploited · CVSS 8.7 High · fixed in 1.8.5 : patch ljharb shell-quote soon.
Data as of 6 Nov 2026, 23:24 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 29% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.8.5
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 25 Jun 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 7 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| ljharbshell-quote | Affected
| Fixed in– |
npmshell-quotepkg:npm/shell-quoteOther 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 fix is available in ljharb shell-quote version 1.8.5. Users should upgrade to version 1.8.5 or later to remediate this vulnerability. No other mitigation is indicated.
Description
shell-quote prior to 1.8.5 finalizes parsed tokens in parse() using Array.prototype.concat as a reduce accumulator, which reallocates and copies the entire growing array on every iteration. As a result parse() runs in O(n^2) time relative to the number of input tokens. An attacker who can supply an attacker-controlled string to any code path that calls parse() (no shell metacharacters are required; plain space-separated words suffice) can block the single-threaded Node.js event loop for an extended period with a small input, resulting in a denial of service. There is no code execution or data disclosure; impact is to availability only. Fixed in 1.8.5.