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CVE-2008-1147
A certain pseudo-random number generator (PRNG) algorithm that uses XOR and 2-bit random hops (aka "Algorithm X2"), as used in OpenBSD 2.6…
Medium6.8EPSS 1.8%
- Published
- Updated
- Reserved
- Assigned by
- mitre
Description
A certain pseudo-random number generator (PRNG) algorithm that uses XOR and 2-bit random hops (aka "Algorithm X2"), as used in OpenBSD 2.6 through 3.4, Mac OS X 10 through 10.5.1, FreeBSD 4.4 through 7.0, and DragonFlyBSD 1.0 through 1.10.1, allows remote attackers to guess sensitive values such as IP fragmentation IDs by observing a sequence of previously generated values. NOTE: this issue can be leveraged for attacks such as injection into TCP packets and OS fingerprinting.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | Medium6.8 | AV:N/AC:M/Au:N/C:P/I:P/A:P |
- EPSS (exploitation in 30 days)
- 1.8% · top 22% of all CVEs (4 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.8.
Weakness
- n/a
Affected products
n/a
- affected n/a
References (10)
- openbsd-xor-weak-security(41155) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- 20080206 RE: A paper by Amit Klein (Trusteer): "OpenBSD DNS Cache Poisoning and Multiple O/S Predictable IP ID Vulnerability" (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 20080206 Re: A paper by Amit Klein (Trusteer): "OpenBSD DNS Cache Poisoning and Multiple O/S Predictable IP ID Vulnerability" (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 20080206 A paper by Amit Klein (Trusteer): "OpenBSD DNS Cache Poisoning and Multiple O/S Predictable IP ID Vulnerability" (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 28819 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- http://www.trusteer.com/docs/OpenBSD_DNS_Cache_Poisoning_and_Multiple_OS_Predictable_IP_ID_Vulnerability.pdf (opens in a new tab)x_refsource_MISCx_transferred
- http://www.securiteam.com/securityreviews/5PP0H0UNGW.html (opens in a new tab)x_refsource_MISCx_transferred
- openbsd-prng-dns-spoofing(40329) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/ip_id.c?rev=1.10%3Bcontenttype= (opens in a new tab)x_refsource_CONFIRMx_transferred
- 27647 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2008-1147)Record last updated .