CVE-2026-0990 | Libxml2: libxml2: denial of service via uncontrolled recursion in xml catalog processing

A flaw was found in libxml2, an XML parsing library. This uncontrolled recursion vulnerability occurs in the xmlCatalogXMLResolveURI function when an XML catalog contains a delegate URI entry that references itself. A remote attacker could exploit this configuration-dependent issue by providing a specially crafted XML catalog, leading to infinite recursion and call stack exhaustion. This ultimately results in a segmentation fault, causing a Denial of Service (DoS) by crashing affected applications.

Published: 2026-01-15 Last update: 2026-04-22 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-0990 is rated Low Risk (29.8/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-0990

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-18 0.18% 0.06% -0.12%
2 2026-01-21 0.14% 0.18% +0.04%
3 2026-01-16 — 0.14% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-0990

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 3.6 [email protected]

Weakness enumeration for CVE-2026-0990

GitHub Security Advisory for CVE-2026-0990

GHSA-2j3v-cxmf-cmp7 · Severity: medium — A flaw was found in libxml2, an XML parsing library. This uncontrolled recursion vulnerability...

OS Trackers for CVE-2026-0990

vendor priority summary link
debian not yet assigned CVE-2026-0990 not yet assigned priority: Debian including 1 source packages (libxml2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-0990
redhat medium — https://access.redhat.com/security/cve/CVE-2026-0990
suse medium CVE-2026-0990 severity moderate: SUSE including 324 source package names (1.1.1-1.29:libxml2-2-2.12.10-150700.4.11.1, 13.2-9.72:libopenssl3-3.1.4-8.1, …), 588 product×package rows across 140 product lines (Container private-registry/harbor-portal, Container suse/ltss/sle12.5/sles12sp5, … (140 product lines)): Fixed 348, Known Affected 231, First Fixed 9. https://www.suse.com/security/cve/CVE-2026-0990/
ubuntu medium CVE-2026-0990 medium priority: Ubuntu including 1 source packages (libxml2), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): released 7, needs-triage 1. https://ubuntu.com/security/CVE-2026-0990

Affected software / configurations for CVE-2026-0990

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-0990

cvelogic Threat Intelligence