CVE-2026-123202
libnxml before 0.18.6 Stack-based Buffer Overflow via long multi-byte XML name
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.
INFO
Published Date :
Nov. 5, 2026, 7:17 p.m.
Last Modified :
Nov. 5, 2026, 7:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-123202
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update libnxml to version 0.18.6 or later.
- Avoid parsing untrusted XML or RSS feeds.
- Validate all XML inputs carefully.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-123202.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-123202 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-123202
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-123202 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-123202 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 05, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-121 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/123xxx/CVE-2026-123202.json">CVE-2026-123202</a> Added Reference https://github.com/bakulf/libnxml/blob/9272d1cd6fee88fe7fd4fd812736d95a6ba25f2f/src/nxml_parser.c#L952-L958 Added Reference https://github.com/bakulf/libnxml/commit/fbac242374883edf2ec14127ca6d2accf4704b6a Added Reference https://github.com/bakulf/libnxml/releases/tag/0.18.6 Added Reference https://www.vulncheck.com/advisories/libnxml-before-0.18.6-stack-based-buffer-overflow-via-long-multi-byte-xml-name -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Nov. 05, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-123202', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-11-05T19:04:41.118484Z'}