CVE-2026-52777

CRITICALPre-NVD 9.49.4—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 88% 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
9.4EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.4Exploit: None knownExposed: 0

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

YesWiki is a wiki system written in PHP. Prior to version 4.6.6, there is an authenticated PHP object injection vulnerability in BazarImportAction via unserialize. This issue has been patched in version 4.6.6.

CVSS v3
9.4
EG Score
9.4(medium)
EG Risk
57(Track)
EG Risk 57/100SSVC: 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
Severity94% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
12%
KEV
Not listed

Published

July 9, 2026

Last Modified

September 8, 2026

Advisory Details (3)

Auto-updated Sep 14, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
github Patch Available🟡 PoC Available

Authenticated PHP Object Injection in BazarImportAction via unserialize · Advisory · YesWiki/yeswiki · GitHub

https://github.com/YesWiki/yeswiki/security/advisories/GHSA-9369-69wj-7m2f
github_release Patch Available

v4.6.6

Patch available: YesWiki/yeswiki v4.6.6

https://github.com/YesWiki/yeswiki/releases/tag/v4.6.6
github_commit Patch Available

commit 8f70a8d6b8be (YesWiki/yeswiki)

Patch available: YesWiki/yeswiki v4.6.6 (contains commit 8f70a8d6b8be)

https://github.com/YesWiki/yeswiki/commit/8f70a8d6b8befa0e644d03c785701dbbc55b8fd0

Vendor Advisories for CVE-2026-52777(1)

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

Affected Packages

(1 across 1 ecosystem)
Packagist(1)
PackageVulnerable rangeFixed inDependents
yeswiki/yeswiki4.2.3 ... v4.6.5 (31 versions)4.6.6—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 19× 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. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 05:34 UTCEG score recompute
  3. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-13 16:55 UTCEG score recompute
  6. 2026-09-13 16:47 UTCEPSS rescore
  7. 2026-09-13 08:17 UTCEG score recompute
  8. 2026-09-12 03:21 UTCEG score recompute
  9. 2026-09-11 14:53 UTCEPSS rescore
  10. 2026-09-10 09:35 UTCEPSS rescore
  11. 2026-09-08 22:53 UTCEG score recompute
  12. 2026-09-08 22:01 UTCEPSS rescore
  13. 2026-09-07 16:01 UTCEPSS rescore
  14. 2026-09-06 13:58 UTCEG score recompute
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-05 22:12 UTCEG score recompute
  17. 2026-09-05 00:19 UTCEG score recompute
  18. 2026-09-04 23:59 UTCEG score recompute▲ 9.40
  19. 2026-09-04 23:59 UTCMITRE cvelistV5CVSS v3 → 9.4 · CVSS v4 → 9.4
  20. 2026-08-01 07:33 UTCEG score recompute
  21. 2026-07-26 12:16 UTCEG score recompute
  22. 2026-07-23 03:19 UTCEG score recompute
  23. 2026-07-09 21:46 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-52777?
CVE-2026-52777 is a critical vulnerability published on July 9, 2026. YesWiki is a wiki system written in PHP. Prior to version 4.6.6, there is an authenticated PHP object injection vulnerability in BazarImportAction via unserialize. This issue has been patched in version 4.6.6.
When was CVE-2026-52777 disclosed?
CVE-2026-52777 was first published in the National Vulnerability Database on July 9, 2026, with the most recent update on September 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52777 actively exploited?
CVE-2026-52777 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 87.8% of all scored CVEs.
What is the CVSS score of CVE-2026-52777?
CVE-2026-52777 has a CVSS v3 base score of 9.4 (NVD).
How do I remediate CVE-2026-52777?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52777, 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-2026-52777

Explore →

Is Your Infrastructure Affected by CVE-2026-52777?

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

Start Free Scan →Browse All CVEs