GnupgApplication

CVE-2026-24881

CRITICAL · 9.8 CVSS v3.1 Published 2026-01-27
Fix available
A fix is available. Upgrade to 2.5.17 / 5.0.1 or later.
See remediation →
100/100
Remediation priority · Urgent
Public exploit Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In GnuPG before 2.5.17, a crafted CMS (S/MIME) EnvelopedData message carrying an oversized wrapped session key can cause a stack-based buffer overflow in gpg-agent during PKDECRYPT--kem=CMS handling. This can easily be leveraged for denial of service; however, there is also memory corruption that could lead to remote code execution.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Stack-based buffer overflow in gpg-agent during PKDECRYPT--kem=CMS handling. A crafted CMS (S/MIME) EnvelopedData message with an oversized wrapped session key overflows a stack buffer, causing denial of service and potential remote code execution via memory corruption.

MitigationUpgrade GnuPG to version 2.5.17 or later to patch the vulnerability. Until then, avoid processing untrusted S/MIME/CMS messages and restrict access to gpg-agent operations.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
GnupgApplication
Affected:>= 2.5.13, < 2.5.17
Gpg4winApplication
Affected:>= 5.0.0, < 5.0.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check if GnuPG is installed
    Run 'gpg --version' or 'gpg2 --version' to display the installed version. On Windows, check Start Menu for Gpg4win or look for installation directory.
    Affected if GnuPG or Gpg4win is installed on the system
  2. Verify the exact GnuPG version
    Parse the version output from 'gpg --version' - look for the version number in the format X.Y.Z (e.g., 2.5.15)
    Affected if The version shown is 2.5.13, 2.5.14, 2.5.15, or 2.5.16 (any version >= 2.5.13 but < 2.5.17)
  3. Verify Gpg4win version if applicable
    Run 'gpgconf --version' or check the Gpg4win installer version. On Windows, check Programs and Features for Gpg4win version.
    Affected if Gpg4win version is 5.0.0 (any version >= 5.0.0 but < 5.0.1)
  4. Confirm gpg-agent availability
    Run 'gpg-agent --version' or 'gpgconf --list-dirs agent-socket' to verify the gpg-agent component is present and accessible.
    Affected if gpg-agent is installed and functional on the system
  5. Check for S/MIME CMS decryption usage
    Review logs or configuration for any use of 'pkdecrypt' operations with 'kem=CMS' or processing of S/MIME EnvelopedData messages.
    Affected if The system processes S/MIME/CMS encrypted messages using GnuPG's PKDECRYPT functionality

The environment is affected if GnuPG version is 2.5.13 through 2.5.16, or Gpg4win version 5.0.0, and the system processes S/MIME/CMS EnvelopedData messages with the gpg-agent component.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.5.17 / 5.0.1 or later
Fixed in 2.5.175.0.1
Interim mitigation

Upgrade GnuPG to version 2.5.17 or later to patch the vulnerability. Until then, avoid processing untrusted S/MIME/CMS messages and restrict access to gpg-agent operations.

Recommended fix High confidence

GnuPG 2.5.17 or later (or latest 2.5.x stable); Gpg4win 5.0.1 or later

  1. Check current GnuPG version using: gpg --version
  2. Upgrade GnuPG to version 2.5.17 or later (or the latest 2.5.x stable release)
  3. For Gpg4win users, upgrade to version 5.0.1 or later
  4. Verify the upgrade was successful by running: gpg --version and confirming the version is >= 2.5.17

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Gnupg Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,280
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,648.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-24881 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data