CVE-2026-25075strongSwan 4.5.0 < 6.0.5 EAP-TTLS AVP Parsing Integer Underflow
- 8.7HighCVSS base score
- 1.1%Exploitation in 30 daysEPSS · top 35% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
strongSwan versions 4.5.0 prior to 6.0.5 contain an integer underflow vulnerability in the EAP-TTLS AVP parser that allows unauthenticated remote attackers to cause a denial of service by sending crafted AVP data with invalid length fields during IKEv2 authentication. Attackers can exploit the failure to validate AVP length fields before subtraction to trigger excessive memory allocation or NULL pointer dereference, crashing the charon IKE daemon.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. 2 references of the record are tagged as an exploit.
Show the exploits2
References tagged exploit2 references
- https://www.strongswan.org/blog/2026/03/23/strongswan-vulnerability-(cve-2026-25075).html (opens in a new tab)vendor-advisoryexploit
- https://y637f9qq2x.com/posts/cve-2026-25075/ (opens in a new tab)technical-descriptionexploit
Timeline
ID reserved
By VulnCheck
- 54 days later
· 54 days later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulnCheckCNA (assigner) | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| VulnCheckCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Deferred | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 1.1% · top 35% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Affected products
- affected 4.5.0 – < 6.0.5
References
References5
- https://www.strongswan.org/blog/2026/03/23/strongswan-vulnerability-(cve-2026-25075).html (opens in a new tab)vendor-advisoryexploit
- https://www.strongswan.org/blog/2026/03/23/strongswan-6.0.5-released.html (opens in a new tab)release-notes
- https://y637f9qq2x.com/posts/cve-2026-25075/ (opens in a new tab)technical-descriptionexploit
- https://www.vulncheck.com/advisories/strongswan-eap-ttls-avp-parsing-integer-underflow (opens in a new tab)third-party-advisory
- https://lists.debian.org/debian-lts-announce/2026/03/msg00016.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-14477 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-25075)Record last updated .