Description
process_http_response in OpenConnect before 8.05 has a Buffer Overflow when a malicious server uses HTTP chunked encoding with crafted chunk sizes.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | openconnect | 8.02-1.1 | — |
| Debian 13 | openconnect | 8.02-1.1 | — |
| Debian 12 | openconnect | 8.02-1.1 | — |
| Debian 10 | openconnect | 8.02-1+deb10u1 | DSA-4607-1 |
| Debian 9 | openconnect | 7.08-1+deb9u1 | DSA-4607-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 8 | openconnect | 6.00-2+deb8u1 | DLA-1945-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | openconnect | 7.08-3ubuntu0.18.04.2 | USN-4565-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | openconnect | 7.08-6.3.1 | SUSE-SU-2019:2737-1 |
| SLES 15 | openconnect | 7.08-6.3.1 | SUSE-SU-2019:2737-1 |
| SLES 12 SP5 | openconnect | 7.08-3.4.1 | SUSE-SU-2019:2744-2 |
| SLES 12 SP4 | openconnect | 7.08-3.4.1 | SUSE-SU-2019:2744-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 15.1 | openconnect | 7.08-lp151.6.3.1 | openSUSE-SU-2019:2385-1 |
| openSUSE Leap 15.0 | openconnect | 7.08-lp150.5.3.1 | openSUSE-SU-2019:2388-1 |
Advisories 8
- USN-4565-1 openconnect vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-4607-1 openconnect - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1945-1 openconnect - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2019:2744-2 Security update for openconnect SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2388-1 Security update for openconnect SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2744-1 Security update for openconnect SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:2737-1 Security update for openconnect SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:2385-1 Security update for openconnect SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://t2.fi/schedule/2019/
- FEDORA-2019-6969467639 vendor-advisory
- http://lists.infradead.org/pipermail/openconnect-devel/2019-September/005412.html
- FEDORA-2019-1caffa01f2 vendor-advisory
- FEDORA-2019-4c0d6e1784 vendor-advisory
- [debian-lts-announce] 20191004 [SECURITY] [DLA 1945-1] openconnect security update mailing-list
- openSUSE-SU-2019:2385 vendor-advisory
- openSUSE-SU-2019:2388 vendor-advisory
- DSA-4607 vendor-advisory
- 20200120 [SECURITY] [DSA 4607-1] openconnect security update mailing-list
- USN-4565-1 vendor-advisory