CVE-2025-66037: opensc_project opensc Out-of-bounds Read
Vulnerability summary
CVE-2025-66037 is a medium (CVSS 6.8) Out-of-bounds Read vulnerability in opensc_project opensc. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.7% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 8 · Related 7Timeline
- 30-03-2026PublishedVulnerability first disclosed.
- 30-03-2026Last modifiedVulnerability information updated.
Description
OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, feeding a crafted input to the fuzz_pkcs15_reader harness causes OpenSC to perform an out-of-bounds heap read in the X.509/SPKI handling path. Specifically, sc_pkcs15_pubkey_from_spki_fields() allocates a zero-length buffer and then reads one byte past the end of that allocation. This issue has been patched in version 0.27.0.
CVSS metrics
4 scores · 4 sources · 1 version- CVE.orgCNA3.9LowCVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:LDiffers
- OSV · UbuntuEcosystem advisory · calculated6.8MediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated6.8MediumCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
16%
Versus all other CVEs
30-day change
0.00 pp
From 0.25% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundOpensc
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Debian1 product
- openscAll versions (No fix recorded) | < 0.27.1-1
Opensc1 product
- opensc< 0.27.0
Opensc_project1 product
- opensc< 0.27.0
Ubuntu1 product
- openscAll versions (No fix recorded)
4 vendors · 4 products
References
6 links- github.com/OpenSC/OpenSC/security/advisories/GHSA-m58q-rmjm-mmfxX Refsource CONFIRMExploitVendor Advisory
