The ShortPixel Image Optimizer – Optimize Images, Convert WebP & AVIF plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 6.5.5 via deserialization of untrusted input . This makes it possible for authenticated attackers, with author-level access and above, to inject a PHP Object. No known POP chain is present in the vulnerable software, which means this vulnerability has no impact unless another plugin or theme containing a POP chain is installed on the site. If a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to perform actions like delete arbitrary files, retrieve sensitive data, or execute code depending on the POP chain present.
CVE-2026-17086
HIGHPre-NVD 8.88.8—Trending — 4 sources updated this week
EchelonGraph scoreHIGH confidence
Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-18. a secondary CVSS source baseline 8.8; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.8Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.8
- EG Score
- 8.8(high)
- EG Risk
- 40(Track)EG Risk 40/100SSVC: 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 computedSeverity88% × 45%Exploitation1% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 58%
- KEV
- Not listed
Published
September 18, 2026
Last Modified
September 18, 2026
References (14)
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/build/shortpixel/replacer2/src/Replacer.php#L259
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/build/shortpixel/replacer2/src/Replacer.php#L402
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/build/shortpixel/replacer2/src/Replacer.php#L425
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/build/shortpixel/replacer2/src/Replacer.php#L429
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/build/shortpixel/replacer2/src/Replacer.php#L446
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.1/class/Controller/Optimizer/OptimizeAiController.php#L598
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/build/shortpixel/replacer2/src/Replacer.php#L259
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/build/shortpixel/replacer2/src/Replacer.php#L402
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/build/shortpixel/replacer2/src/Replacer.php#L425
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/build/shortpixel/replacer2/src/Replacer.php#L429
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/build/shortpixel/replacer2/src/Replacer.php#L446
- security@wordfencehttps://plugins.trac.wordpress.org/browser/shortpixel-image-optimiser/tags/6.5.4/class/Controller/Optimizer/OptimizeAiController.php#L598
- security@wordfencehttps://plugins.trac.wordpress.org/changeset?reponame=&old=3688579%40shortpixel-image-optimiser&new=3688579%40shortpixel-image-optimiser
- security@wordfencehttps://www.wordfence.com/threat-intel/vulnerabilities/id/89ef2ee1-2bec-459f-9a85-c260cbb129ca?source=cve
Vendor Advisories for CVE-2026-17086(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 18× in last 7d / 18× 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.
- 2026-09-21 05:28 UTCEG score recompute
- 2026-09-21 05:28 UTCGHSA enrichment
- 2026-09-20 17:03 UTCGHSA enrichment
- 2026-09-20 04:37 UTCGHSA enrichment
- 2026-09-19 16:12 UTCEG score recompute
- 2026-09-19 16:12 UTCGHSA enrichment
- 2026-09-19 03:47 UTCEG score recompute
- 2026-09-19 03:47 UTCGHSA enrichment
- 2026-09-18 19:27 UTCEPSS rescore
- 2026-09-18 15:23 UTCEG score recompute
- 2026-09-18 15:23 UTCGHSA enrichment
- 2026-09-18 14:34 UTCEG score recompute
- 2026-09-18 14:34 UTCGHSA enrichment
- 2026-09-18 13:39 UTCEG score recompute
- 2026-09-18 13:39 UTCGHSA enrichment
- 2026-09-18 04:34 UTCEG score recompute
- 2026-09-18 03:49 UTCEG score recompute
- 2026-09-18 03:49 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Same CWE
10 shownCWE-502
Frequently asked(5)
What is CVE-2026-17086?
CVE-2026-17086 is a high vulnerability published on September 18, 2026. The ShortPixel Image Optimizer – Optimize Images, Convert WebP & AVIF plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 6.5.5 via deserialization of untrusted input . This makes it possible for authenticated attackers, with author-level access and…
When was CVE-2026-17086 disclosed?
CVE-2026-17086 was first published in the National Vulnerability Database on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-17086 actively exploited?
CVE-2026-17086 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 42.2% of all scored CVEs.
What is the CVSS score of CVE-2026-17086?
CVE-2026-17086 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-17086?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-17086, 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-2026-17086
Is Your Infrastructure Affected by CVE-2026-17086?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.