CVE-2026-5260 | Gnutls: gnutls: information disclosure via heap overread in rsa key exchange

A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret during an RSA key exchange to a server using an RSA key backed by a PKCS#11 token, could trigger a short heap overread. This memory corruption vulnerability could lead to information disclosure.

Published: 2026-05-26 Last update: 2026-06-02 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-5260 is rated Moderate Risk (46/100): CVSS High severity, with low exploitation likelihood (EPSS 0.17%). Mandatory action: Review affected assets and schedule remediation.

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-2026-5260

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 2026-06-01 0.14% 0.17% +0.03%
2 2026-05-27 0.14%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-5260

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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:L)
Some sensitive info could get out, but not a total data dump.
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 4.2 [email protected]

Weakness enumeration for CVE-2026-5260

GitHub Security Advisory for CVE-2026-5260

GHSA-6hj5-4cv5-f46x · Severity: high — A flaw was found in libgnutls. A remote attacker, by sending an extremely short premaster secret...

OS Trackers for CVE-2026-5260

vendor priority summary link
debian not yet assigned CVE-2026-5260 not yet assigned priority: Debian including 1 source packages (gnutls28), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-5260
suse medium https://www.suse.com/security/cve/CVE-2026-5260/
ubuntu medium CVE-2026-5260 medium priority: Ubuntu including 1 source packages (gnutls28), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, resolute, upstream, xenial): released 5, needs-triage 3. https://ubuntu.com/security/CVE-2026-5260

Affected software / configurations for CVE-2026-5260

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-5260

cvelogic Threat Intelligence