Description
crypto/bn/bn_nist.c in OpenSSL before 0.9.8h on 32-bit platforms, as used in stunnel and other products, in certain circumstances involving ECDH or ECDHE cipher suites, uses an incorrect modular reduction algorithm in its implementation of the P-256 and P-384 NIST elliptic curves, which allows remote attackers to obtain the private key of a TLS server via multiple handshake attempts.
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 | 0.9.8o-4squeeze3 | — |
| Debian 13 | openssl | 0.9.8o-4squeeze3 | — |
| Debian 12 | openssl | 0.9.8o-4squeeze3 | — |
| Debian 6.0 | openssl | 0.9.8o-4squeeze5 | DSA-2390-1 |
| Debian 5.0 | openssl | 0.9.8g-15+lenny15 | DSA-2390-1 |
Advisories 1
- DSA-2390-1 openssl - several Debian Security (DSA / DLA) · Mar 9, 2026
References
- http://crypto.di.uminho.pt/CACE/CT-RSA2012-openssl-src.zip
- https://bugzilla.redhat.com/show_bug.cgi?id=757909
- [oss-security] 20111201 CVE-2011-4354 OpenSSL 0.9.8g (32-bit builds) bug leaks ECC private keys mailing-list
- http://eprint.iacr.org/2011/633
- http://rt.openssl.org/Ticket/Display.html?id=1593&user=guest&pass=guest
- http://cvs.openssl.org/filediff?f=openssl/crypto/bn/bn_nist.c&v1=1.14&v2=1.21
- DSA-2390 vendor-advisory
- http://marc.info/?t=119271238800004