CVE-2025-11849: mammoth · Directory Traversal
Affects mammothSource CVE Database V5
Not known to be exploited · CVSS 6.4 Medium : upgrade to 1.11.0 when convenient.
Data as of 26 Oct 2026, 07:57 UTC
- EPSS
- 1.1% chance of exploitation in 30 days – higher than 66% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.11.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:H/SI:N/SA:H/E:PExploitation evidence
Disclosed: evidence found.
CVE published 17 Oct 2025
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 2026-10-26.
What to do
Upgrade mammoth and org.zwobble.mammoth to 1.11.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
npmmammothpkg:npm/mammothOther threats | Affected
| Fixed in
|
PyPImammothpkg:pypi/mammothOther threats | Affected
| Fixed in
|
NuGetmammothpkg:nuget/mammothOther threats | Affected
| Fixed in
|
Mavenorg.zwobble.mammothpkg:maven/org.zwobble.mammothOther 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
1. Upgrade mammoth to version 1.11.0 or later where this vulnerability is fixed. 2. Implement strict validation and sanitization of DOCX files before processing, rejecting files with external image links or suspicious r:link attributes. 3. Run document conversion processes in isolated, sandboxed environments with minimal file system permissions to limit access to sensitive files. 4. Monitor and log document processing activities to detect anomalous file access patterns. 5. Employ rate limiting and resource usage controls to mitigate potential denial of service from resource exhaustion. 6. Educate users and administrators about the risks of processing untrusted DOCX files and enforce policies restricting document sources. 7. Consider using alternative libraries or tools with stronger security postures if mammoth is not essential.
Description
Versions of the package mammoth from 0.3.25 and before 1.11.0; versions of the package mammoth from 0.3.25 and before 1.11.0; versions of the package mammoth before 1.11.0; versions of the package org.zwobble.mammoth:mammoth before 1.11.0 are vulnerable to Directory Traversal due to the lack of path or file type validation when processing a docx file containing an image with an external link (r:link attribute instead of embedded r:embed). The library resolves the URI to a file path and after reading, the content is encoded as base64 and included in the HTML output as a data URI. An attacker can read arbitrary files on the system where the conversion is performed or cause an excessive resources consumption by crafting a docx file that links to special device files such as /dev/random or /dev/zero.
References
- security.snyk.io/vuln/SNYK-JS-MAMMOTH-13554470 (opens in a new tab)
- security.snyk.io/vuln/SNYK-PYTHON-MAMMOTH-13561967 (opens in a new tab)
- security.snyk.io/vuln/SNYK-DOTNET-MAMMOTH-13561968 (opens in a new tab)
- security.snyk.io/vuln/SNYK-JAVA-ORGZWOBBLEMAMMOTH-13561969 (opens in a new tab)
- gist.github.com/AudunWA/4d690d9ae5efdafe7cf71d9c2ee90a10 (opens in a new tab)
- github.com/mwilliamson/mammoth.js/commit/c54aaeb43a7941317c1f3c119ffa92090f988820 (opens in a new tab)