Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traffic, aka a "backtracking attack."
Published Jan 16, 2007
5.0
MEDIUMCVSS 2.0
EPSS 2.39%
Description
Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traffic, aka a "backtracking attack."
Affected products
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (15 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.39% (0.02386) | 83.32th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.31% (0.02312) | 81.09th | v5 (v2026.06.15) |
| Feb 9, 2026 | 4.69% (0.04694) | 89.09th | v4 (v2025.03.14) |
| Mar 17, 2025 | 3.55% (0.03552) | 86.90th | v4 (v2025.03.14) |
| Dec 12, 2024 | 13.75% (0.13746) | 95.85th | v3 (v2023.03.01) |
| Mar 13, 2024 | 13.75% (0.13746) | 95.47th | v3 (v2023.03.01) |
| Dec 28, 2023 | 11.35% (0.11353) | 94.67th | v3 (v2023.03.01) |
| Nov 20, 2023 | 14.25% (0.14247) | 95.17th | v3 (v2023.03.01) |
| Oct 13, 2023 | 15.56% (0.15563) | 95.28th | v3 (v2023.03.01) |
| Sep 5, 2023 | 16.29% (0.16290) | 95.31th | v3 (v2023.03.01) |
| Jun 20, 2023 | 16.55% (0.16555) | 95.26th | v3 (v2023.03.01) |
| Mar 7, 2023 | 12.86% (0.12865) | 94.56th | v3 (v2023.03.01) |
| Mar 6, 2023 | 3.78% (0.03779) | 85.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 3.78% (0.03779) | 84.01th | v2 (v2022.01.01) |
| Feb 4, 2022 | 3.78% (0.03779) | 67.21th | v2 (v2022.01.01) |
No CWE recorded.
References (16)
- http://lists.immunitysec.com/pipermail/dailydave/2007-January/003954.html mailing-listx_refsource_MLIST
- http://secunia.com/advisories/23716 third-party-advisoryx_refsource_SECUNIA
- http://secunia.com/advisories/24164 third-party-advisoryx_refsource_SECUNIA
- http://secunia.com/advisories/24338 third-party-advisoryx_refsource_SECUNIA
- http://security.gentoo.org/glsa/glsa-200702-03.xml vendor-advisoryx_refsource_GENTOO
- http://securitytracker.com/id?1017508 vdb-entryx_refsource_SECTRACK
- http://www.acsac.org/2006/abstracts/54.html x_refsource_MISC
- http://www.acsac.org/2006/advance_program.html x_refsource_MISC
- http://www.acsac.org/2006/papers/54.pdf x_refsource_MISCVendor Advisory
- http://www.cs.wisc.edu/~smithr/pubs/acsac2006.pdf x_refsource_MISCVendor Advisory
- http://www.cs.wisc.edu/~smithr/pubs/randy_smith_acsac2006.zip x_refsource_MISC
- http://www.mandriva.com/security/advisories?name=MDKSA-2007:051 vendor-advisoryx_refsource_MANDRIVA
- http://www.osvdb.org/32096 vdb-entryx_refsource_OSVDB
- http://www.securityfocus.com/bid/21991 vdb-entryx_refsource_BID
- http://www.snort.org/pub-bin/snortnews.cgi x_refsource_CONFIRM
- https://exchange.xforce.ibmcloud.com/vulnerabilities/31430 vdb-entryx_refsource_XF
Change history (0)
No recorded changes yet.