CVE-2026-25075
CVE-2026-25075 · strongSwan 4.5.0 < 6.0.5 EAP-TTLS AVP Parsing Integer Underflow
This page contains facts from public vulnerability sources. Check the original advisory before updating.
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.
CVSS 8.7 · High · EPSS 1.1% · Fix available
- Published
- Updated
Stack: system
Affected products and versions
strongswan
- Versions
- ≥ 4.5.0, < 6.0.5: Affected (semver)
Update to 6.0.5
strongswan Debian:12
- Versions
- 5.9.8-5
- 5.9.8-5+deb12u1
- 5.9.8-5+deb12u2
- Affected ranges
- ECOSYSTEM: < 5.9.8-5+deb12u3
Update to 5.9.8-5+deb12u3
strongswan Debian:13
- Versions
- 6.0.1-6
- 6.0.1-6+deb13u1
- 6.0.1-6+deb13u2
- Affected ranges
- ECOSYSTEM: < 6.0.1-6+deb13u4
Update to 6.0.1-6+deb13u4
strongswan Debian:14
- Versions
- 6.0.1-6
- 6.0.2-1
- 6.0.3-1
- 6.0.4-1
- Affected ranges
- ECOSYSTEM: < 6.0.5-1
Update to 6.0.5-1
strongswan Ubuntu:Pro:14.04:LTS
- Versions
- 4.6.4-9
- 5.1.0-2
- 5.1.0-3
- 5.1.1-0ubuntu1
- 5.1.1-0ubuntu2
- 5.1.1-0ubuntu3
- 5.1.1-0ubuntu4
- 5.1.1-0ubuntu5
- 5.1.1-0ubuntu7
- 5.1.1-0ubuntu14
- 5.1.1-0ubuntu17
- 5.1.2~dr3+git20130120-0ubuntu2
- 5.1.2~dr3+git20130120-0ubuntu3
- 5.1.2~rc1-0ubuntu3
- 5.1.2~rc1-0ubuntu4
- 5.1.2~rc2-0ubuntu2
- 5.1.2-0ubuntu1
- 5.1.2-0ubuntu2
- 5.1.2-0ubuntu2.2
- 5.1.2-0ubuntu2.3
- 5.1.2-0ubuntu2.4
- 5.1.2-0ubuntu2.5
- 5.1.2-0ubuntu2.6
- 5.1.2-0ubuntu2.7
- 5.1.2-0ubuntu2.8
- 5.1.2-0ubuntu2.10
- 5.1.2-0ubuntu2.11
- 5.1.2-0ubuntu2.11+esm1
- 5.1.2-0ubuntu2.11+esm2
- 5.1.2-0ubuntu2.11+esm3
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:16.04:LTS
- Versions
- 5.1.2-0ubuntu6
- 5.1.2-0ubuntu7
- 5.1.2-0ubuntu8
- 5.3.5-1ubuntu1
- 5.3.5-1ubuntu2
- 5.3.5-1ubuntu3
- 5.3.5-1ubuntu3.1
- 5.3.5-1ubuntu3.2
- 5.3.5-1ubuntu3.3
- 5.3.5-1ubuntu3.4
- 5.3.5-1ubuntu3.5
- 5.3.5-1ubuntu3.7
- 5.3.5-1ubuntu3.8
- 5.3.5-1ubuntu3.8+esm1
- 5.3.5-1ubuntu3.8+esm2
- 5.3.5-1ubuntu3.8+esm3
- 5.3.5-1ubuntu3.8+esm4
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS-updates:16.04:LTS
- Versions
- 5.3.5-1ubuntu3.fips.3.4.1
- 5.3.5-1ubuntu3.fips.3.4.2
- 5.3.5-1ubuntu3.fips.3.8.1
- 5.3.5-1ubuntu3.fips.3.8.2
- 5.3.5-1ubuntu3.fips.3.8.3
- 5.3.5-1ubuntu3.fips.3.8.6
- 5.3.5-1ubuntu3.fips.3.8.7
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS:16.04:LTS
- Versions
- 5.3.5-1ubuntu3.fips.3.1
- 5.3.5-1ubuntu3.fips.3.2
- 5.3.5-1ubuntu3.fips.3.3
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:18.04:LTS
- Versions
- 5.5.1-4ubuntu2
- 5.5.1-4ubuntu3
- 5.6.1-2ubuntu1
- 5.6.1-2ubuntu2
- 5.6.1-2ubuntu3
- 5.6.1-2ubuntu4
- 5.6.2-1ubuntu2
- 5.6.2-1ubuntu2.2
- 5.6.2-1ubuntu2.3
- 5.6.2-1ubuntu2.4
- 5.6.2-1ubuntu2.5
- 5.6.2-1ubuntu2.6
- 5.6.2-1ubuntu2.7
- 5.6.2-1ubuntu2.8
- 5.6.2-1ubuntu2.9
- 5.6.2-1ubuntu2.9+esm1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS-updates:18.04:LTS
- Versions
- 5.6.2-1ubuntu2.fips.2.5.1
- 5.6.2-1ubuntu2.fips.2.7.1
- 5.6.2-1ubuntu2.fips.2.7.2
- 5.6.2-1ubuntu2.fips.2.8.1
- 5.6.2-1ubuntu2.fips.2.9
- 5.6.2-1ubuntu2.fips.2.9+esm1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS:18.04:LTS
- Versions
- 5.6.2-1ubuntu2.fips.2.4.2
- 5.6.2-1ubuntu2.fips.2.5.1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:20.04:LTS
- Versions
- 5.7.2-1ubuntu3
- 5.8.1-1ubuntu1
- 5.8.2-1ubuntu1
- 5.8.2-1ubuntu2
- 5.8.2-1ubuntu3
- 5.8.2-1ubuntu3.1
- 5.8.2-1ubuntu3.2
- 5.8.2-1ubuntu3.3
- 5.8.2-1ubuntu3.4
- 5.8.2-1ubuntu3.5
- 5.8.2-1ubuntu3.6
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS-updates:20.04:LTS
- Versions
- 5.8.2-1ubuntu3.fips.3.1.2
- 5.8.2-1ubuntu3.fips.3.3.1
- 5.8.2-1ubuntu3.fips.3.4.1
- 5.8.2-1ubuntu3.fips.3.5
- 5.8.2-1ubuntu3.fips.3.6
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS:20.04:LTS
- Versions
- 5.8.2-1ubuntu3.fips.3.1.2
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:22.04:LTS
- Versions
- 5.9.1-1ubuntu3
- 5.9.1-1ubuntu3.1
- 5.9.4-1ubuntu1
- 5.9.4-1ubuntu2
- 5.9.4-1ubuntu3
- 5.9.4-1ubuntu4
- 5.9.5-2ubuntu1
- 5.9.5-2ubuntu2
- 5.9.5-2ubuntu2.1
- 5.9.5-2ubuntu2.2
- 5.9.5-2ubuntu2.3
- 5.9.5-2ubuntu2.4
- Affected ranges
- ECOSYSTEM: < 5.9.5-2ubuntu2.5
Update to 5.9.5-2ubuntu2.5
strongswan Ubuntu:Pro:FIPS-preview:22.04:LTS
- Versions
- 5.9.5-2ubuntu2.1+Fips1
- 5.9.5-2ubuntu2.2+Fips1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
strongswan Ubuntu:Pro:FIPS-updates:22.04:LTS
- Versions
- 5.9.5-2ubuntu2.1+Fips1
- 5.9.5-2ubuntu2.2+Fips1
- 5.9.5-2ubuntu2.3+Fips1
- 5.9.5-2ubuntu2.4+Fips1
- Affected ranges
- ECOSYSTEM: < 5.9.5-2ubuntu2.5+Fips1
Update to 5.9.5-2ubuntu2.5+Fips1
strongswan Ubuntu:24.04:LTS
- Versions
- 5.9.11-1ubuntu1
- 5.9.11-1ubuntu2
- 5.9.12-1ubuntu1
- 5.9.13-2ubuntu1
- 5.9.13-2ubuntu3
- 5.9.13-2ubuntu4
- 5.9.13-2ubuntu4.24.04.1
- Affected ranges
- ECOSYSTEM: < 5.9.13-2ubuntu4.24.04.2
Update to 5.9.13-2ubuntu4.24.04.2
strongswan Ubuntu:25.10
- Versions
- 5.9.13-2ubuntu4
- 5.9.13-2ubuntu5
- 6.0.1-6ubuntu2
- 6.0.1-6ubuntu4
- 6.0.1-6ubuntu4.1
- Affected ranges
- ECOSYSTEM: < 6.0.1-6ubuntu4.2
Update to 6.0.1-6ubuntu4.2
Original sources
- https://www.strongswan.org/blog/2026/03/23/strongswan-vulnerability-(cve-2026-25075).html
- https://www.strongswan.org/blog/2026/03/23/strongswan-6.0.5-released.html
- https://y637f9qq2x.com/posts/cve-2026-25075/
- https://www.vulncheck.com/advisories/strongswan-eap-ttls-avp-parsing-integer-underflow
- https://lists.debian.org/debian-lts-announce/2026/03/msg00016.html
- https://nvd.nist.gov/vuln/detail/CVE-2026-25075