CVE-2025-68973 — Out-of-bounds Write in Gnupg
In GnuPG before 2.4.9, armor_filter in g10/armor.c has two increments of an index variable where one is intended, leading to an out-of-bounds write for crafted input. (For ExtendedLTS, 2.2.51 and later are fixed versions.)
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (high)+6
- CISA SSVC: exploitation "poc"+5
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
- Documented patch — github.com (NIST National Vulnerability Database)
- Documented patch — www.openwall.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Gnupg Gnupg).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.4 | 5.8 | cve@mitre.org via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | mitre via CVE Program (cve.org) e CISA ADP |
| 7.0 | CVSS 3.1 | High | 1.0 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.16%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · gnupg/gnupg
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 7.0
- Source status changed · → Modified
- Record created in this database
- 2025
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
9 on the record
- github.com/gpg/gnupg/compare/gnupg-2.2.50...gnupg-2.2.51
- www.openwall.com/lists/oss-security/2025/12/29/11
- github.com/gpg/gnupg/commit/115d138ba599328005c5321c0ef9f00355838ca9
- gpg.fail/memcpy
- www.openwall.com/lists/oss-security/2025/12/28/5
- news.ycombinator.com/item
- media.ccc.de/v/39c3-to-sign-or-not-to-sign-practical-vulnerabilities-i
- github.com/gpg/gnupg/blob/ff30683418695f5d2cc9e6cf8c9418e09378ebe4/g10/armor.c
- lists.debian.org/debian-lts-announce/2026/01/msg00008.html
Elsewhere on this site
Related CVEs (same products)
- Low CVE-2026-105712 gpgtar in GnuPG before 2.5.19 can allow file overwrite via crafted data in an archive… 10d
- Low CVE-2026-57062 CMS (Cryptographic Message Syntax) parsing in gpgsm in GnuPG through 2.5.20 mishandles… Jun 23, 2026
- Critical CVE-2026-24881 GnuPG gpg-agent Stack-based Buffer Overflow in CMS Decryption Jan 27, 2026
- High CVE-2026-24882 Stack-based Buffer Overflow in Gnupg Jan 27, 2026
- Medium CVE-2026-24883 NULL Pointer Dereference in Gnupg Jan 27, 2026
- Medium CVE-2025-68972 Improper Verification of Cryptographic Signature in Gnupg Dec 27, 2025
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2025-68973 is "Out-of-bounds Write in Gnupg", rated High. It affects Gnupg (Gnupg); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.0 describes technical severity. EPSS 0.15% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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