CVE-2025-68973
Out-of-Bounds Write in GnuPG Armor Filter (g10/armor.c
Publication date: 2025-12-28
Last updated on: 2025-12-28
Assigner: MITRE
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| gnupg | gnupg | 2.4.8 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-675 | The product performs the same operation on a resource two or more times, when the operation should only be applied once. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in GnuPG through version 2.4.8 involves the armor_filter function in the g10/armor.c file, where an index variable is incremented twice instead of once as intended. This causes an out-of-bounds write when processing specially crafted input, potentially leading to memory corruption.
How can this vulnerability impact me? :
The out-of-bounds write caused by this vulnerability can lead to memory corruption, which may be exploited to cause unexpected behavior such as crashes or potentially allow an attacker to execute arbitrary code with the privileges of the GnuPG process.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
The provided resources do not explicitly discuss the impact of CVE-2025-68973 on compliance with common standards and regulations such as GDPR or HIPAA. However, given that the vulnerability allows potential plaintext recovery and memory corruption in GnuPG, a widely used cryptographic tool for secure communications and data protection, it could indirectly affect compliance by undermining the confidentiality and integrity of encrypted data. Organizations relying on GnuPG for encryption might face increased risk of data exposure, which could lead to non-compliance with data protection regulations that mandate strong encryption and protection of personal or sensitive data. Nonetheless, no direct statements or analyses regarding regulatory compliance impacts are provided in the resources. [1, 5]
How can this vulnerability be detected on my network or system? Can you suggest some commands?
Detection of CVE-2025-68973 involves identifying attempts to exploit the memory corruption in GnuPG's ASCII-armor parsing, particularly crafted inputs that trigger the double increment bug in the armor_filter function. A practical approach includes running GnuPG with debugging symbols and using proof-of-concept (PoC) payloads designed to trigger the vulnerability, as demonstrated in Resource 3. Tools like Valgrind can be used to detect uninitialized memory access and buffer overflows when processing suspicious armored messages. Monitoring for abnormal errors such as zlib errors during decryption or unexpected behavior in GnuPG's armor processing may also indicate exploitation attempts. Specific commands include compiling GnuPG with debugging enabled and running it against crafted payload files to observe crashes or memory errors. However, no simple network scanning commands are provided in the resources. Therefore, detection primarily relies on controlled testing with PoCs and memory analysis tools. [3]
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include applying the official patch that fixes the double increment bug in the armor_filter function, as detailed in Resource 2. This patch corrects the loop increment logic to prevent out-of-bounds writes and adds assertions to detect improper buffer handling. Users should update GnuPG to a version that includes this fix (post-2.4.8). Additionally, users are advised to avoid decrypting or processing untrusted or suspicious ASCII-armored messages, especially those that might be crafted to exploit this vulnerability. Considering the broader security context, users may also consider minimizing reliance on PGP/GnuPG for email encryption due to inherent design weaknesses highlighted in Resource 1 and Resource 5, and explore alternative secure messaging platforms where feasible. However, the critical immediate action is to update GnuPG with the provided patch to eliminate the memory corruption risk. [1, 2, 5]