CVE-2026-52777

CRITICALPre-NVD 9.49.4
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This critical-severity CVE scores 9.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (18th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source
9.4EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 9.4Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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
9.4CRITICALmedium confidence
EG Risk
57
EG Risk 57/100

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 (value × EchelonGraph’s weight)
Severity94% × 45%
The EG Score, 9.4 of 10.
Exploitation0.3% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
0.3%
EPSS %ILE
18th
KEV
Not listed

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation none (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 9, 2026

Last Modified

September 8, 2026

Advisory Details (3)

Auto-updated Oct 2, 2026
Patch available. Sources: github_commit, github_release, github.
GitHub advisoryMentions a patch (unverified)

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 rangeFix by version rangeDependents
yeswiki/yeswiki4.2.3 ... v4.6.5 (31 versions)
  • every version up to 4.6.6: fixed in 4.6.6
—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 35× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-10-14 01:59 UTCEG score recompute
  2. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  3. 2026-10-12 22:17 UTCEG score recompute
  4. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  5. 2026-10-12 15:58 UTCEG score recompute
  6. 2026-10-11 19:41 UTCEG score recompute
  7. 2026-10-11 16:56 UTCEG score recompute
  8. 2026-10-11 14:19 UTCEG score recompute
  9. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  10. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  11. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  12. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  13. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  14. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  15. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  16. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  17. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  18. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  19. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  20. 2026-10-01 16:01 UTCEG score recompute
  21. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  22. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  23. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  24. 2026-09-28 10:26 UTCEG score recompute
  25. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 18th percentile
Show 29 more
  1. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  2. 2026-09-26 00:27 UTCEPSS rescoreEPSS 0.3% · 17th percentile
  3. 2026-09-24 11:23 UTCEG score recompute
  4. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  5. 2026-09-23 05:53 UTCEG score recompute
  6. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  7. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  8. 2026-09-18 05:34 UTCEG score recompute
  9. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  10. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  11. 2026-09-13 16:55 UTCEG score recompute
  12. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  13. 2026-09-13 08:17 UTCEG score recompute
  14. 2026-09-12 03:21 UTCEG score recompute
  15. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  16. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  17. 2026-09-08 22:53 UTCEG score recompute
  18. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  19. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  20. 2026-09-06 13:58 UTCEG score recompute
  21. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 11th percentile
  22. 2026-09-05 22:12 UTCEG score recompute
  23. 2026-09-05 00:19 UTCEG score recompute
  24. 2026-09-04 23:59 UTCEG score recomputeFirst assessed: 9.4 CRITICAL
  25. 2026-09-04 23:59 UTCMITRE cvelistV5CVSS v3 → 9.4 · CVSS v4 → 9.4
  26. 2026-08-01 07:33 UTCEG score recompute
  27. 2026-07-26 12:16 UTCEG score recompute
  28. 2026-07-23 03:19 UTCEG score recompute
  29. 2026-07-09 21:46 UTCEG score recompute

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-52777?
CVE-2026-52777 is a critical-severity vulnerability; its CVE record was 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 the CVE record for CVE-2026-52777 published?
The CVE record for CVE-2026-52777 was published on July 9, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 8, 2026; the record at its source may have been updated since.
Is CVE-2026-52777 actively exploited?
CVE-2026-52777 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (18th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-52777?
CVE-2026-52777 has a CVSS base score of 9.4 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-52777?
A fix for CVE-2026-52777 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-52777 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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