libnxml before 0.18.6 contains a stack-based buffer overflow vulnerability in src/nxml_parser.c that allows remote attackers to write past a 1024-byte stack buffer via long XML names
Source GCVE Database
Not known to be exploited · CVSS 8.7 High : upgrade to 0.18.6 soon.
Data as of 5 Nov 2026, 22:34 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.7 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 7.5 |
- Patch
- Available – fixed in 0.18.6
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 5 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 libnxml to 0.18.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| bakulflibnxml | Affected
| Fixed in
|
GitHublibnxmlpkg:github/libnxmlOther 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
libnxml before 0.18.6 contains a stack-based buffer overflow vulnerability in src/nxml_parser.c that allows remote attackers to write past a 1024-byte stack buffer via long XML names. Attackers can supply XML or RSS feeds with a 1022-character element, attribute, DOCTYPE or entity name ending in a multi-byte UTF-8 character to crash parsing applications.
References
- nvd.nist.gov/vuln/detail/CVE-2026-123202 (opens in a new tab)
- github.com/bakulf/libnxml/commit/fbac242374883edf2ec14127ca6d2accf4704b6a (opens in a new tab)
- github.com/bakulf/libnxml/blob/9272d1cd6fee88fe7fd4fd812736d95a6ba25f2f/src/nxml_parser.c (opens in a new tab)
- github.com/bakulf/libnxml/releases/tag/0.18.6 (opens in a new tab)
- vulncheck.com/advisories/libnxml-before-0.18.6-stack-based-buffer-overflow-via-long-multi-byte-xml-name (opens in a new tab)