CVE-2026-45186

Exp

In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.

Published: 2026-05-10 Last update: 2026-05-14 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-45186 is rated Exploit Available (50/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.00%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2026-45186

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-45186

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 2026-05-10 — 0.00% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-45186

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.9 3.1 LOW
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.4 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/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:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
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.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-45186

GitHub Security Advisory for CVE-2026-45186

GHSA-r396-2q2c-pjhr · Severity: low — In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows...

OS Trackers for CVE-2026-45186

vendor priority summary link
debian not yet assigned CVE-2026-45186 not yet assigned priority: Debian including 1 source packages (expat), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-45186
suse low — https://www.suse.com/security/cve/CVE-2026-45186/
ubuntu medium CVE-2026-45186 medium priority: Ubuntu including 23 source packages (apache2, apr-util, …), 178 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 92, not-affected 56, DNE 25, ignored 5. https://ubuntu.com/security/CVE-2026-45186

Affected software / configurations for CVE-2026-45186

Vendor Product Version Raw CPE
libexpat_project libexpat < 2.8.1 cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*

References for CVE-2026-45186

URL Tags
https://github.com/libexpat/libexpat/pull/1216 Exploit Issue Tracking Patch
http://www.openwall.com/lists/oss-security/2026/05/11/16 Mailing List Third Party Advisory
cvelogic Threat Intelligence