CVE-2026-53938

HIGHPre-NVD 8.28.2—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.2 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 85% 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, secondary
8.2EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.2Exploit: None knownExposed: 0

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

OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). Prior to version 0.6.2.5, cjose's JWE decryption path for the AES Key Wrap key-management algorithms (alg = A128KW, A192KW, A256KW) does not validate the length of the attacker-supplied encrypted_key (JWE Encrypted Key) before unwrapping it into a fixed-size, heap-allocated Content Encryption Key (CEK) buffer. A remote, unauthenticated attacker who can submit a crafted JWE to an application that decrypts it with an AES-KW symmetric key can trigger an out-of-bounds heap write, corrupting the heap. This leads at minimum to a crash (denial of service) and, depending on the heap layout and allocator, may be leverageable for further memory-corruption impact. cjose_jwe_import() / cjose_jwe_decrypt() are pre-authentication entry points: they parse and process fully attacker-controlled input. Upgrade to cjose 0.6.2.5 to receive a patch. If upgrading is not immediately possible, reject the AES Key Wrap algorithms (A128KW/A192KW/A256KW) for untrusted JWEs at the application layer.

CVSS v3
8.2
EG Score
8.2(medium)
EG Risk
52(Track)
EG Risk 52/100SSVC: 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
Severity82% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
15%
KEV
Not listed

Published

September 8, 2026

Last Modified

September 10, 2026

Advisory Details (2)

Auto-updated Sep 8, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit.
github_commit

commit 8c51d2452735 (OpenIDC/cjose)

Fix landed in OpenIDC/cjose commit 8c51d2452735 — awaiting tagged release

https://github.com/OpenIDC/cjose/commit/8c51d245273583a658f24ef7b08ba22f848a34a5
github Patch Available🟡 PoC Available

Heap buffer overflow in AES Key Wrap decryption (A128KW/A192KW/A256KW) · Advisory · OpenIDC/cjose · GitHub

https://github.com/OpenIDC/cjose/security/advisories/GHSA-75r7-f5cv-g3wj

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 24× 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. 2026-09-21 06:52 UTCEG score recompute
  2. 2026-09-20 20:16 UTCEPSS rescore
  3. 2026-09-19 17:26 UTCEG score recompute
  4. 2026-09-19 04:57 UTCEG score recompute
  5. 2026-09-18 19:28 UTCEPSS rescore
  6. 2026-09-18 03:59 UTCEG score recompute
  7. 2026-09-17 19:31 UTCEPSS rescore
  8. 2026-09-17 02:55 UTCEG score recompute
  9. 2026-09-16 14:08 UTCEPSS rescore
  10. 2026-09-16 13:54 UTCEG score recompute
  11. 2026-09-16 05:15 UTCEPSS rescore
  12. 2026-09-15 12:21 UTCEG score recompute
  13. 2026-09-13 22:54 UTCEG score recompute
  14. 2026-09-13 16:47 UTCEPSS rescore
  15. 2026-09-12 21:56 UTCEG score recompute
  16. 2026-09-11 20:58 UTCEG score recompute
  17. 2026-09-11 14:53 UTCEPSS rescore
  18. 2026-09-10 18:33 UTCEG score recompute
  19. 2026-09-10 09:35 UTCEPSS rescore
  20. 2026-09-09 17:31 UTCEG score recompute
  21. 2026-09-09 16:46 UTCEG score recompute
  22. 2026-09-09 00:35 UTCEG score recompute
  23. 2026-09-08 23:34 UTCEG score recompute
  24. 2026-09-08 23:33 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-53938?
CVE-2026-53938 is a high vulnerability published on September 8, 2026. OpenIDC/cjose is a C library implementing the Javascript Object Signing and Encryption (JOSE). Prior to version 0.6.2.5, cjose's JWE decryption path for the AES Key Wrap key-management algorithms (alg = A128KW, A192KW, A256KW) does not validate the length of the attacker-supplied encryptedkey (JWE…
When was CVE-2026-53938 disclosed?
CVE-2026-53938 was first published in the National Vulnerability Database on September 8, 2026, with the most recent update on September 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53938 actively exploited?
CVE-2026-53938 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 85.1% of all scored CVEs.
What is the CVSS score of CVE-2026-53938?
CVE-2026-53938 has a CVSS v3 base score of 8.2 (NVD).
How do I remediate CVE-2026-53938?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53938, 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

Explore the affected products and dependency analysis for CVE-2026-53938

Explore →

Is Your Infrastructure Affected by CVE-2026-53938?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs