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 t
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.
- Published
- Mar 4, 2008
- Updated
- Jun 16, 2026
- EPSS
- 1.8% · 77th percentile
- CWE
- —
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Report tools
Action score
28
Monitor
Low priority for now.
- CVSS
- 27 / 40 · 6.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 1.8%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| openbsd | openbsd | cpe:2.3:o:openbsd:openbsd |
| apple | mac os x | cpe:2.3:o:apple:mac_os_x |
| apple | mac os x server | cpe:2.3:o:apple:mac_os_x_server |
| dragonflybsd | dragonflybsd | cpe:2.3:o:dragonflybsd:dragonflybsd |
| freebsd | freebsd | cpe:2.3:o:freebsd:freebsd |
| netbsd | netbsd | cpe:2.3:o:netbsd:netbsd |
| cosmicperl | directory pro | cpe:2.3:a:cosmicperl:directory_pro |
| darwin | darwin | cpe:2.3:a:darwin:darwin |
| navision | financials server | cpe:2.3:a:navision:financials_server |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cosmicperl directory pro10.0.3
- darwin darwin1.0
- darwin darwin9.1
- navision financials server3.0
Same product
openbsd: all recordsOther highest-scoring records for the same primary product.
- CVE-2007-5365Stack-based buffer overflow in the cons_options function in options.c in dhcpd in OpenBSD 4.0 through 4.2, and some other dhcpd implementati52Plan
- CVE-2007-1365Buffer overflow in kern/uipc_mbuf2.c in OpenBSD 3.9 and 4.0 allows remote attackers to execute arbitrary code via fragmented IPv6 packets du45Plan
- CVE-2004-0220isakmpd in OpenBSD 3.4 and earlier allows remote attackers to cause a denial of service via an ISAKMP packet with a malformed Cert Request p41Plan
- CVE-2001-0284Buffer overflow in IPSEC authentication mechanism for OpenBSD 2.8 and earlier allows remote attackers to cause a denial of service and possi41Plan
- CVE-2000-1010Format string vulnerability in talkd in OpenBSD and possibly other BSD-based OSes allows remote attackers to execute arbitrary commands via 41Plan
- CVE-2020-16088iked in OpenIKED, as used in OpenBSD through 6.7, allows authentication bypass because ca.c has the wrong logic for checking whether a publi40Plan
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
If successful
- Confidentiality
- P · data can be read
- Integrity
- P · data or configuration can be modified
- Availability
- P · the service can be disrupted
- Attack complexity
- M
- Confidentiality impact
- P
- Integrity impact
- P
- Availability impact
- P
Weakness class (CWE)
—
CVSS vector
AV:N/AC:M/Au:N/C:P/I:P/A:P
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
- seclists.org/bugtraq/2008/Feb/0052.html
- seclists.org/bugtraq/2008/Feb/0063.html
- secunia.com/advisories/28819
- www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/ip_id.c?rev=1.10%3Bcontenttype=
- www.securiteam.com/securityreviews/5PP0H0UNGW.html
- www.securityfocus.com/archive/1/487658
- www.securityfocus.com/bid/27647
- www.trusteer.com/docs/OpenBSD_DNS_Cache_Poisoning_and_Multiple_OS_Predictable_IP_ID_Vulnerability.pdf
- exchange.xforce.ibmcloud.com/vulnerabilities/40329
- exchange.xforce.ibmcloud.com/vulnerabilities/41155
Vendor advisories and official records. Exploit/PoC links are deliberately left out.