CVE-2025-66038

MEDIUMNVD 6.86.8—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.8 under NVD CVSS v3. EPSS exploit probability: 0.3%, top 79% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Elevated
6.8EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.8Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
6.8
EG Score
6.8(medium)
EG Risk
47(Track)
EG Risk 47/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity68% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

March 30, 2026

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Aug 3, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
generic

CVE 2025 66038 · OpenSC/OpenSC Wiki · GitHub

https://github.com/OpenSC/OpenSC/wiki/CVE-2025-66038
github Patch Available🟡 PoC Available

`sc_compacttlv_find_tag` can return out-of-bounds pointers · Advisory · OpenSC/OpenSC · GitHub

https://github.com/OpenSC/OpenSC/security/advisories/GHSA-72x5-fwjx-2459
github_commit

commit 6db171bcb6fd (OpenSC/OpenSC)

Fix landed in OpenSC/OpenSC commit 6db171bcb6fd — awaiting tagged release

https://github.com/OpenSC/OpenSC/commit/6db171bcb6fd7cb3b51098fefbb3b28e44f0a79c

Vendor Advisories for CVE-2025-66038(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
opensc0.21.0-1 ... 0.27.1-2 (23 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
opensc0.23.0-0.3 ... 0.27.1-2 (18 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
opensc0.26.1-2 ... 0.27.1-2 (6 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
opensc0.26.1-2, 0.26.1-30.27.0~rc1-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 29× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-15 03:10 UTCEPSS rescore
  2. 2026-09-13 16:46 UTCEPSS rescore
  3. 2026-09-12 15:00 UTCEPSS rescore
  4. 2026-09-11 14:52 UTCEPSS rescore
  5. 2026-09-11 09:36 UTCEPSS rescore
  6. 2026-09-10 09:34 UTCEPSS rescore
  7. 2026-09-08 22:00 UTCEPSS rescore
  8. 2026-09-07 16:00 UTCEPSS rescore
  9. 2026-09-06 13:47 UTCEPSS rescore
  10. 2026-09-04 05:06 UTCEPSS rescore
  11. 2026-09-02 14:11 UTCEPSS rescore
  12. 2026-09-02 12:44 UTCOSV refresh
  13. 2026-09-01 13:53 UTCEPSS rescore
  14. 2026-08-30 19:16 UTCEPSS rescore
  15. 2026-08-30 01:21 UTCEPSS rescore
  16. 2026-08-28 21:40 UTCEPSS rescore
  17. 2026-08-27 14:24 UTCEPSS rescore
  18. 2026-08-26 14:45 UTCEPSS rescore
  19. 2026-08-25 13:48 UTCEPSS rescore
  20. 2026-08-24 14:16 UTCEPSS rescore
  21. 2026-08-23 00:18 UTCEPSS rescore
  22. 2026-08-21 23:48 UTCEPSS rescore
  23. 2026-08-20 22:55 UTCEPSS rescore
  24. 2026-08-19 17:03 UTCEPSS rescore
  25. 2026-08-18 13:47 UTCEPSS rescore
Show 46 more
  1. 2026-08-17 13:46 UTCEPSS rescore
  2. 2026-08-16 14:55 UTCEPSS rescore
  3. 2026-08-16 09:46 UTCEG score recompute
  4. 2026-08-16 09:46 UTCVendor advisory
  5. 2026-08-16 02:13 UTCEPSS rescore
  6. 2026-08-15 01:30 UTCEPSS rescore
  7. 2026-08-15 01:29 UTCEPSS rescore
  8. 2026-08-14 06:09 UTCEG score recompute
  9. 2026-08-14 06:09 UTCVendor advisory
  10. 2026-08-13 21:59 UTCEPSS rescore
  11. 2026-08-12 20:29 UTCEG score recompute
  12. 2026-08-12 20:29 UTCVendor advisory
  13. 2026-08-12 13:50 UTCEPSS rescore
  14. 2026-08-11 13:42 UTCEPSS rescore
  15. 2026-08-11 08:30 UTCEG score recompute
  16. 2026-08-11 08:30 UTCVendor advisory
  17. 2026-08-10 23:59 UTCEPSS rescore
  18. 2026-08-10 07:08 UTCEG score recompute
  19. 2026-08-10 07:08 UTCVendor advisory
  20. 2026-08-09 13:46 UTCEPSS rescore
  21. 2026-08-09 13:46 UTCEPSS rescore
  22. 2026-08-09 05:43 UTCEG score recompute
  23. 2026-08-09 05:43 UTCVendor advisory
  24. 2026-08-08 16:36 UTCEPSS rescore
  25. 2026-08-07 16:26 UTCEPSS rescore
  26. 2026-08-07 15:54 UTCEG score recompute
  27. 2026-08-07 15:54 UTCVendor advisory
  28. 2026-08-06 13:46 UTCEPSS rescore
  29. 2026-08-06 00:40 UTCEG score recompute
  30. 2026-08-06 00:40 UTCVendor advisory
  31. 2026-08-05 19:17 UTCEPSS rescore
  32. 2026-08-05 19:17 UTCEPSS rescore
  33. 2026-08-04 15:09 UTCEPSS rescore
  34. 2026-08-04 10:37 UTCEPSS rescore
  35. 2026-08-03 23:00 UTCEG score recompute
  36. 2026-08-03 10:35 UTCEPSS rescore
  37. 2026-08-02 15:03 UTCEG score recompute▲ 2.90
  38. 2026-08-02 15:03 UTCVendor advisory
  39. 2026-08-02 02:26 UTCEPSS rescore
  40. 2026-08-01 04:15 UTCEPSS rescore
  41. 2026-07-30 16:27 UTCEPSS rescore
  42. 2026-07-30 01:30 UTCEPSS rescore
  43. 2026-07-28 15:35 UTCEPSS rescore
  44. 2026-07-27 14:12 UTCEPSS rescore
  45. 2026-07-27 12:52 UTCEG score recompute
  46. 2026-07-27 12:52 UTCVendor advisory

Frequently asked(5)

What is CVE-2025-66038?
CVE-2025-66038 is a medium vulnerability published on March 30, 2026. OpenSC is an open source smart card tools and middleware. Prior to version 0.27.0, sccompacttlvfindtag 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…
When was CVE-2025-66038 disclosed?
CVE-2025-66038 was first published in the National Vulnerability Database on March 30, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2025-66038 actively exploited?
CVE-2025-66038 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.4% of all scored CVEs.
What is the CVSS score of CVE-2025-66038?
CVE-2025-66038 has a CVSS v3 base score of 6.8 (NVD).
How do I remediate CVE-2025-66038?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2025-66038, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2025-66038

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