Description
The ASN1 library in OpenSSL 0.9.6d and earlier, and 0.9.7-beta2 and earlier, allows remote attackers to cause a denial of service via invalid encodings.
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 | openssl | 0.9.6e-1 | — |
| Debian 13 | openssl | 0.9.6e-1 | — |
| Debian 12 | openssl | 0.9.6e-1 | — |
| Debian 3.0 | openssl | 0.9.6c-2.woody.0 | DSA-136-2, DSA-136-1 |
| Debian 3.0 | openssl094 | 0.9.4-6.woody.0 | DSA-136-3, DSA-136-2, DSA-136-1 |
| Debian 3.0 | openssl095 | 0.9.5a-6.woody.0 | DSA-136-2, DSA-136-1 |
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
- OpenSSL - ASN.1 Parsing EDB-23199 · remote · Oct 9, 2003 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 3
- DSA-136-3 openssl - multiple remote exploits Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-136-1 openssl - multiple remote exploits Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-136-2 openssl - multiple remote exploits Debian Security (DSA / DLA) · Mar 9, 2026
References
- RHSA-2002:164 vendor-advisory
- RHSA-2002:161 vendor-advisory
- VU#748355 third-party-advisory
- CA-2002-23 third-party-advisory
- RHSA-2002:160 vendor-advisory
- openssl-asn1-parser-dos(9718) vdb-entry
- CLA-2002:516 vendor-advisory
- 5366 vdb-entry