CVE-2026-33845: gnu gnutls Integer Underflow (Wrap or Wraparound)
CVSS: 9.1v3.1CriticalModified
AliasesALPINE-CVE-2026-33845UBUNTU-CVE-2026-33845DEBIAN-CVE-2026-33845
Published 30-04-2026Last modified 14-10-2026
Vulnerability summary
CVE-2026-33845 is a critical (CVSS 9.1) Integer Underflow (Wrap or Wraparound) vulnerability in gnu gnutls. EPSS estimates a 0.89% chance of exploitation in the next 30 days, higher than 58.6% of scored vulnerabilities.
CVSS score
9.1/10
010
Critical · v3.1 (NVD)EPSS score
0.89%
0%100%
Low · +0.08 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 17 · Related 6Timeline
- 30-04-2026PublishedVulnerability first disclosed.
- 14-10-2026Last modifiedVulnerability information updated.
Description
A flaw in GnuTLS DTLS handshake parsing allows malformed fragments with zero length and non-zero offset, leading to an integer underflow during reassembly and resulting in an out-of-bounds read. This issue is remotely exploitable and may cause information disclosure or denial of service.
CVSS metrics
5 scores · 5 sources · 1 versionCritical 9.1Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HSources5 sources · 7.5–9.1
- CVE.orgCNA7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HDiffers
- OSV · AlpineEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
- OSV · DebianEcosystem advisory · calculated9.1CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
EPSS trend
Probability
0.89%
Chance of exploitation in the next 30 days
Percentile
59%
Versus all other CVEs
30-day change
+0.08 pp
From 0.80% on 19-09-2026
19-09-202619-10-2026
EPSS score0.89%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Redhat2 products
- enterprise_linuxEOL6.0 | 7.0 | 8.0 | 9.0 | 10.0
- openshift_container_platform4.0
Alpine1 product
- gnutls< 3.8.13-r0
Debian1 product
- gnutls28< 3.7.9-2+deb12u7 | < 3.8.9-3+deb13u4 | < 3.8.13-1
Gnu1 product
- gnutlsna
Ubuntu1 product
- gnutls28< 3.6.13-2ubuntu1.12+esm2 | < 3.7.3-4ubuntu1.9 | All versions (No fix recorded) | < 3.7.3-4ubuntu1.9+Fips1 | < 3.8.3-1.1ubuntu3.6 | < 3.8.3-1.1ubuntu3.6+Fips1.2 | < 3.8.9-3ubuntu2.2 | < 3.8.12-2ubuntu1.1
5 vendors · 6 products
