CVE-2026-88896

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreHIGH confidence

Score 5.3 from GitHub Security Advisory published 2026-09-10. a secondary CVSS source baseline 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
5.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.3Exploit: None knownExposed: 0

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

EspoCRM before 10.0.4 is vulnerable to server-side request forgery. HostCheck::ipAddressIsNotInternal(), which validates outbound URLs to block requests to internal/private IP addresses, strips ::ffff: (IPv4-mapped IPv6) prefixes but does not recognize IPv6 transition addresses that embed private IPv4 addresses: NAT64 (64:ff9b::), 6to4 (2002::), and Teredo (2001:0000::). An attacker who controls a domain with AAAA records pointing to such transition addresses can bypass both the internal-host validation and the CURLOPT_RESOLVE IP-pinning check, causing EspoCRM to issue outbound requests to internal network services. Affected paths include POST /Attachment/fromImageUrl, reachable by any authenticated user with attachment access, and outbound webhook delivery, which requires an admin or API user.

CVSS v3
5.3
EG Score
5.3(high)
EG Risk
39(Track)
EG Risk 39/100SSVC: 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
Severity53% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
27%
KEV
Not listed

Published

September 10, 2026

Last Modified

September 15, 2026

Advisory Details (2)

Auto-updated Sep 10, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

EspoCRM before 10.0.4 SSRF via IPv6 Transition Address Bypass | Advisories | VulnCheck

https://www.vulncheck.com/advisories/espocrm-before-10.0.4-ssrf-via-ipv6-transition-address-bypass
github Patch Available🟡 PoC Available

SSRF via IPv6 transition address bypass of internal-host validation · Advisory · espocrm/espocrm · GitHub

https://github.com/espocrm/espocrm/security/advisories/GHSA-xwmh-j8hf-cfqw

Vendor Advisories for CVE-2026-88896(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 21× in last 7d / 34× 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. 2026-09-20 22:52 UTCEG score recompute
  2. 2026-09-20 22:51 UTCGHSA enrichment
  3. 2026-09-20 20:16 UTCEPSS rescore
  4. 2026-09-19 22:05 UTCEG score recompute
  5. 2026-09-19 22:05 UTCGHSA enrichment
  6. 2026-09-18 21:19 UTCEG score recompute
  7. 2026-09-18 21:19 UTCGHSA enrichment
  8. 2026-09-18 19:28 UTCEPSS rescore
  9. 2026-09-17 19:50 UTCEG score recompute
  10. 2026-09-17 19:50 UTCGHSA enrichment
  11. 2026-09-17 19:32 UTCEPSS rescore
  12. 2026-09-16 18:09 UTCEG score recompute
  13. 2026-09-16 18:09 UTCGHSA enrichment
  14. 2026-09-16 14:09 UTCEPSS rescore
  15. 2026-09-16 05:15 UTCEPSS rescore
  16. 2026-09-15 15:34 UTCEG score recompute
  17. 2026-09-15 15:34 UTCGHSA enrichment
  18. 2026-09-15 14:35 UTCEG score recompute
  19. 2026-09-15 14:35 UTCGHSA enrichment
  20. 2026-09-15 03:12 UTCEPSS rescore
  21. 2026-09-14 18:28 UTCGHSA enrichment
  22. 2026-09-13 17:39 UTCEG score recompute
  23. 2026-09-13 17:39 UTCGHSA enrichment
  24. 2026-09-13 16:48 UTCEPSS rescore
  25. 2026-09-12 16:53 UTCEG score recompute
Show 9 more
  1. 2026-09-12 16:53 UTCGHSA enrichment
  2. 2026-09-12 15:02 UTCEPSS rescore
  3. 2026-09-11 16:07 UTCEG score recompute
  4. 2026-09-11 16:07 UTCGHSA enrichment
  5. 2026-09-11 14:53 UTCEPSS rescore
  6. 2026-09-11 14:53 UTCEPSS rescore
  7. 2026-09-10 14:19 UTCEG score recompute
  8. 2026-09-10 13:20 UTCEG score recompute
  9. 2026-09-10 13:20 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-88896?
CVE-2026-88896 is a medium vulnerability published on September 10, 2026. EspoCRM before 10.0.4 is vulnerable to server-side request forgery. HostCheck::ipAddressIsNotInternal(), which validates outbound URLs to block requests to internal/private IP addresses, strips ::ffff: (IPv4-mapped IPv6) prefixes but does not recognize IPv6 transition addresses that embed private…
When was CVE-2026-88896 disclosed?
CVE-2026-88896 was first published in the National Vulnerability Database on September 10, 2026, with the most recent update on September 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-88896 actively exploited?
CVE-2026-88896 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 73.0% of all scored CVEs.
What is the CVSS score of CVE-2026-88896?
CVE-2026-88896 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-88896?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-88896, 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

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