CVE-2008-3656
Algorithmic complexity vulnerability in the WEBrick::HTTPUtils.split_header_value function in WEBrick::HTTP::DefaultFileHandler in WEBrick…
- 7.8HighCVSS base score
- 70.2%Exploitation in 30 daysEPSS · top 0.6% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- 2Public exploitsMetasploit, Nuclei and Exploit-DB
Description
Algorithmic complexity vulnerability in the WEBrick::HTTPUtils.split_header_value function in WEBrick::HTTP::DefaultFileHandler in WEBrick in Ruby 1.8.5 and earlier, 1.8.6 through 1.8.6-p286, 1.8.7 through 1.8.7-p71, and 1.9 through r18423 allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted HTTP request that is processed by a backtracking regular expression.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module and an Exploit-DB entry for it.
Show the exploits2
Metasploit modules1 module
- Ruby WEBrick::HTTP::DefaultFileHandler DoS (Metasploit module) (opens in a new tab)
auxiliary/dos/http/webrick_regexRank normaldisclosed 8 Aug 2008
Exploit-DB1 entry
- Ruby 1.9 - 'WEBrick::HTTP::DefaultFileHandler' Crafted HTTP Request Denial of Service (Exploit-DB entry) (opens in a new tab)
EDB-ID 32222dos, multiplepublished 11 Aug 2008Verified
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By mitre
- 1 day later
· 1 day later
Published
- 16 years later
· 16 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 2.0 | High7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
- EPSS (exploitation in 30 days)
- 70.2% · top 0.6% of all CVEs (10 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
n/a
- affected n/a
References
30
- oval:org.mitre.oval:def:9682 (opens in a new tab)vdb-entrysignaturex_refsource_OVALx_transferred
- 31430 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- 31697 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- USN-651-1 (opens in a new tab)vendor-advisoryx_refsource_UBUNTUx_transferred
- ruby-webrick-dos(44371) (opens in a new tab)vdb-entryx_refsource_XFx_transferred
- http://support.apple.com/kb/HT3549 (opens in a new tab)x_refsource_CONFIRMx_transferred
- http://wiki.rpath.com/wiki/Advisories:rPSA-2008-0264 (opens in a new tab)x_refsource_CONFIRMx_transferred
- DSA-1652 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- FEDORA-2008-8736 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- 35074 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- http://support.avaya.com/elmodocs2/security/ASA-2008-424.htm (opens in a new tab)x_refsource_CONFIRMx_transferred
- DSA-1651 (opens in a new tab)vendor-advisoryx_refsource_DEBIANx_transferred
- APPLE-SA-2009-05-12 (opens in a new tab)vendor-advisoryx_refsource_APPLEx_transferred
- 30644 (opens in a new tab)vdb-entryx_refsource_BIDx_transferred
- RHSA-2008:0897 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
- http://www.ruby-lang.org/en/news/2008/08/08/multiple-vulnerabilities-in-ruby/ (opens in a new tab)x_refsource_CONFIRMx_transferred
- 32219 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- 1020654 (opens in a new tab)vdb-entryx_refsource_SECTRACKx_transferred
- TA09-133A (opens in a new tab)third-party-advisoryx_refsource_CERTx_transferred
- 32255 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- ADV-2009-1297 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
- 20080831 rPSA-2008-0264-1 ruby (opens in a new tab)mailing-listx_refsource_BUGTRAQx_transferred
- 32371 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- 32165 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- GLSA-200812-17 (opens in a new tab)vendor-advisoryx_refsource_GENTOOx_transferred
- 33178 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_transferred
- ADV-2008-2334 (opens in a new tab)vdb-entryx_refsource_VUPENx_transferred
- FEDORA-2008-8738 (opens in a new tab)vendor-advisoryx_refsource_FEDORAx_transferred
- http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=494401 (opens in a new tab)x_refsource_CONFIRMx_transferred
- 32256 (opens in a new tab)third-party-advisoryx_refsource_SECUNIAx_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)
- EUVD EUVD-2008-3642 (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://cveledger.app/cve/CVE-2008-3656)Record last updated .