CVE-2025-66038

3.9 LOW
Published: March 30, 2026 Modified: April 01, 2026
View on NVD

Description

OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, sc_compacttlv_find_tag searches a compact-TLV buffer for a given tag. In compact-TLV, a single byte encodes the tag (high nibble) and value length (low nibble). With a 1-byte buffer {0x0A}, the encoded element claims tag=0 and length=10 but no value bytes follow. Calling sc_compacttlv_find_tag with search tag 0x00 returns a pointer equal to buf+1 and outlen=10 without verifying that the claimed value length fits within the remaining buffer. In cases where the sc_compacttlv_find_tag is provided untrusted data (such as being read from cards/files), attackers may be able to influence it to return out-of-bounds pointers leading to downstream memory corruption when subsequent code tries to dereference the pointer. This issue has been patched in version 0.27.0.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://github.com/OpenSC/OpenSC/security/advisories/GHSA-72x5-fwjx-2459
Source: security-advisories@github.com
Exploit Vendor Advisory
https://github.com/OpenSC/OpenSC/wiki/CVE-2025-66038
Source: security-advisories@github.com
Vendor Advisory

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
3.9 / 10.0
EPSS (Exploit Probability)
0.0%
6th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

opensc_project