CVE-2026-15341

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-15. a secondary CVSS source baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

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

The User Session Synchronizer plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.4.0. The synchronize_session() function, hooked on init and therefore executed on every request, performs no nonce, capability, or shared-secret validation against the attacker-supplied ussync-key, ussync-token, and ussync-ref parameters; when ussync-key references an unregistered slot, get_option() returns false for both the secret key and the domain list, causing the AES-256-CBC encryption key to degrade to the fully predictable md5('') and the referer allowlist to collapse to an empty-string match, while the AES IV is unconditionally hard-coded as md5('another-secret'). This makes it possible for unauthenticated attackers to supply a crafted request encrypting any known or guessable user email address in the ussync-ref parameter, causing the handler to call wp_set_auth_cookie() for the matched user and granting full authentication as that user — including administrators — with no prior knowledge of site secrets.

CVSS v3
9.8
EG Score
9.8(high)
EG Risk
49(Track)
EG Risk 49/100SSVC: 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
Severity98% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
26%
KEV
Not listed

Published

August 15, 2026

Last Modified

August 20, 2026

References (7)

Vendor Advisories for CVE-2026-15341(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 53× in last 7d / 53× 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. 2026-08-21 05:08 UTCGHSA enrichment
  2. 2026-08-21 01:07 UTCEG score recompute
  3. 2026-08-21 01:07 UTCGHSA enrichment
  4. 2026-08-20 22:55 UTCEPSS rescore
  5. 2026-08-20 21:05 UTCGHSA enrichment
  6. 2026-08-20 17:05 UTCGHSA enrichment
  7. 2026-08-20 13:03 UTCGHSA enrichment
  8. 2026-08-20 10:28 UTCGHSA enrichment
  9. 2026-08-20 06:28 UTCGHSA enrichment
  10. 2026-08-20 02:27 UTCGHSA enrichment
  11. 2026-08-19 22:26 UTCGHSA enrichment
  12. 2026-08-19 18:25 UTCEG score recompute
  13. 2026-08-19 18:25 UTCGHSA enrichment
  14. 2026-08-19 17:03 UTCEPSS rescore
  15. 2026-08-19 13:07 UTCGHSA enrichment
  16. 2026-08-19 09:06 UTCGHSA enrichment
  17. 2026-08-19 05:06 UTCGHSA enrichment
  18. 2026-08-19 01:04 UTCGHSA enrichment
  19. 2026-08-18 21:03 UTCGHSA enrichment
  20. 2026-08-18 17:02 UTCEG score recompute
  21. 2026-08-18 17:02 UTCGHSA enrichment
  22. 2026-08-18 13:48 UTCEPSS rescore
  23. 2026-08-18 12:41 UTCGHSA enrichment
  24. 2026-08-18 08:35 UTCGHSA enrichment
  25. 2026-08-18 04:33 UTCGHSA enrichment
Show 28 more
  1. 2026-08-18 00:30 UTCGHSA enrichment
  2. 2026-08-17 20:26 UTCGHSA enrichment
  3. 2026-08-17 16:25 UTCGHSA enrichment
  4. 2026-08-17 15:31 UTCEG score recompute
  5. 2026-08-17 15:31 UTCGHSA enrichment
  6. 2026-08-17 13:47 UTCEPSS rescore
  7. 2026-08-17 11:30 UTCGHSA enrichment
  8. 2026-08-17 07:29 UTCGHSA enrichment
  9. 2026-08-17 03:29 UTCGHSA enrichment
  10. 2026-08-16 23:28 UTCGHSA enrichment
  11. 2026-08-16 19:27 UTCGHSA enrichment
  12. 2026-08-16 15:26 UTCEG score recompute
  13. 2026-08-16 15:26 UTCGHSA enrichment
  14. 2026-08-16 14:56 UTCEPSS rescore
  15. 2026-08-16 11:25 UTCGHSA enrichment
  16. 2026-08-16 07:24 UTCGHSA enrichment
  17. 2026-08-16 03:24 UTCEG score recompute
  18. 2026-08-16 03:24 UTCGHSA enrichment
  19. 2026-08-16 02:14 UTCEPSS rescore
  20. 2026-08-15 23:23 UTCGHSA enrichment
  21. 2026-08-15 19:22 UTCGHSA enrichment
  22. 2026-08-15 15:21 UTCGHSA enrichment
  23. 2026-08-15 11:20 UTCGHSA enrichment
  24. 2026-08-15 07:19 UTCEG score recompute
  25. 2026-08-15 07:19 UTCGHSA enrichment
  26. 2026-08-15 03:18 UTCEG score recompute
  27. 2026-08-15 02:41 UTCEG score recompute
  28. 2026-08-15 02:40 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-15341?
CVE-2026-15341 is a critical vulnerability published on August 15, 2026. The User Session Synchronizer plugin for WordPress is vulnerable to Authentication Bypass leading to Account Takeover in all versions up to, and including, 1.4.0. The synchronizesession() function, hooked on init and therefore executed on every request, performs no nonce, capability, or…
When was CVE-2026-15341 disclosed?
CVE-2026-15341 was first published in the National Vulnerability Database on August 15, 2026, with the most recent update on August 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-15341 actively exploited?
CVE-2026-15341 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 73.6% of all scored CVEs.
What is the CVSS score of CVE-2026-15341?
CVE-2026-15341 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-15341?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-15341, 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-2026-15341

Explore →

Is Your Infrastructure Affected by CVE-2026-15341?

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

Start Free Scan →Browse All CVEs