CVE-2025-15467

Published Jan 27, 2026

Last updated a day ago

OpenSSL

CMS AuthEnvelopedData

Overview

AI description

Automated description summarized from trusted sources.

CVE-2025-15467 is a stack buffer overflow vulnerability found in OpenSSL, specifically within its parsing of CMS AuthEnvelopedData. This flaw arises when OpenSSL processes Cryptographic Message Syntax (CMS) structures that utilize Authenticated Encryption with Associated Data (AEAD) ciphers, such as AES-GCM. The library fails to adequately verify that the length of the Initialization Vector (IV) fits into a fixed-size stack buffer. An attacker can exploit this vulnerability by sending a specially crafted CMS message containing an oversized IV. This can lead to a crash, resulting in a Denial of Service (DoS), or potentially enable remote code execution. The overflow occurs prior to any authentication or tag verification, meaning that no valid key material is required to trigger the issue. This vulnerability impacts OpenSSL versions 3.0 through 3.6.

Description: Issue summary: Parsing CMS AuthEnvelopedData message with maliciously crafted AEAD parameters can trigger a stack buffer overflow. Impact summary: A stack buffer overflow may lead to a crash, causing Denial of Service, or potentially remote code execution. When parsing CMS AuthEnvelopedData structures that use AEAD ciphers such as AES-GCM, the IV (Initialization Vector) encoded in the ASN.1 parameters is copied into a fixed-size stack buffer without verifying that its length fits the destination. An attacker can supply a crafted CMS message with an oversized IV, causing a stack-based out-of-bounds write before any authentication or tag verification occurs. Applications and services that parse untrusted CMS or PKCS#7 content using AEAD ciphers (e.g., S/MIME AuthEnvelopedData with AES-GCM) are vulnerable. Because the overflow occurs prior to authentication, no valid key material is required to trigger it. While exploitability to remote code execution depends on platform and toolchain mitigations, the stack-based write primitive represents a severe risk. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not affected by this issue, as the CMS implementation is outside the OpenSSL FIPS module boundary. OpenSSL 3.6, 3.5, 3.4, 3.3 and 3.0 are vulnerable to this issue. OpenSSL 1.1.1 and 1.0.2 are not affected by this issue.
Source: openssl-security@openssl.org
NVD status: Received

Weaknesses

openssl-security@openssl.org: CWE-787

Hype score is a measure of social media activity compared against trending CVEs from the past 12 months. Max score 100.

Hype score: 35

References

Sources include official advisories and independent security research.

Overview

AI description

Weaknesses

Social media

References