Description
FastCGI (aka fcgi and libfcgi) 2.4.0 allows remote attackers to cause a denial of service (segmentation fault and crash) via a large number of connections.
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 | libfcgi | 2.4.0-8.3 | — |
| Debian 14 | libfcgi-perl | 0.78-2 | — |
| Debian 13 | libfcgi | 2.4.0-8.3 | — |
| Debian 13 | libfcgi-perl | 0.78-2 | — |
| Debian 12 | libfcgi | 2.4.0-8.3 | — |
| Debian 12 | libfcgi-perl | 0.78-2 | — |
| Debian 6.0 | libfcgi | 2.4.0-8+deb6u1 | DLA-430-1 |
| Debian 6.0 | libfcgi-perl | 0.71-1+squeeze1+deb6u1 | DLA-431-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | fcgi | 2.4.0-7 | — |
| Azure Linux 2 (CBL-Mariner) | fcgi | 2.4.0-7 | — |
Advisories 2
- DLA-431-1 libfcgi-perl - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-430-1 libfcgi - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1189958
- https://bugs.launchpad.net/ubuntu/+source/libfcgi/+bug/933417
- http://advisories.mageia.org/MGASA-2015-0184.html
- [oss-security] 20150207 Re: CVE request for denial-of-service vulnerability in fcgi mailing-list
- libfcgi-connections-dos(100696) vdb-entry
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=681591
- [oss-security] 20150206 CVE request for denial-of-service vulnerability in fcgi mailing-list