Description
Linux kernel 2.4.x and 2.6.x for x86 allows local users to cause a denial of service (system crash), possibly via an infinite loop that triggers a signal handler with a certain sequence of fsave and frstor instructions, as originally demonstrated using a "crash.c" program.
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 3.0 | kernel-image-sparc-2.4 | 26woody1 | DSA-1070-1 |
| Debian 3.0 | kernel-patch-2.4.19-mips | 2.4.19-0.020911.1.woody5 | DSA-1070-1 |
| Debian 3.0 | kernel-source-2.4.16 | 2.4.16-1woody2 | DSA-1067-1 |
| Debian 3.0 | kernel-source-2.4.17 | 2.4.17-1woody4 | DSA-1082-1 |
| Debian 3.0 | kernel-source-2.4.18 | 2.4.18-14.4 | DSA-1069-1 |
| Debian 3.0 | kernel-source-2.4.19 | 2.4.19-4.woody3 | DSA-1070-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 3 | kernel +8 | 2.4.21-15.0.2.EL | RHSA-2004:255 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- Linux Kernel 2.4.x/2.6.x - Assembler Inline Function Local Denial of Service EDB-306 · dos · Jun 25, 2004 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 5
- RHSA-2004:255 Red Hat Security Advisory: kernel security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- DSA-1082-1 kernel-source-2.4.17 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1067-1 kernel-source-2.4.16 - several Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1069-1 kernel-source-2.4.18 - several Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-1070-1 kernel-source-2.4.19 - several vulnerabilities Debian Security (DSA / DLA) · Mar 9, 2026
References
- 20163 third-party-advisory
- VU#973654 third-party-advisory
- oval:org.mitre.oval:def:9426 vdb-entry signature
- DSA-1082 vendor-advisory
- RHSA-2004:255 vendor-advisory
- http://linuxreviews.org/news/2004-06-11_kernel_crash/index.html
- 10538 vdb-entry
- RHSA-2004:260 vendor-advisory
- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15905
- SuSE-SA:2004:017 vendor-advisory
- 2004-0034 vendor-advisory
- DSA-1070 vendor-advisory
- FEDORA-2004-186 vendor-advisory
- 20162 third-party-advisory
- 20040620 TSSA-2004-011 - kernel mailing-list
- ESA-20040621-005 vendor-advisory
- CLA-2004:845 vendor-advisory
- DSA-1067 vendor-advisory
- linux-dos(16412) vdb-entry
- DSA-1069 vendor-advisory
- oval:org.mitre.oval:def:2915 vdb-entry signature
- MDKSA-2004:062 vendor-advisory
- 20202 third-party-advisory
- GLSA-200407-02 vendor-advisory
- [linux-kernel] 20040609 timer + fpu stuff locks my console race mailing-list
- 20338 third-party-advisory