apr: hash table collisions CPU usage DoS
Published Feb 10, 2012
5.0
MEDIUMCVSS 2.0
EPSS 42.14%
Description
tables/apr_hash.c in the Apache Portable Runtime (APR) library through 1.4.5 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted input to an application that maintains a hash table.
Affected products
No data.
- ≤ 1.4.5
- 0.9.1
- 0.9.2
- 0.9.2-dev
- 0.9.3
- 0.9.3-dev
- 0.9.4
- 0.9.5
- 0.9.6
- 0.9.7
- 0.9.7-dev
- 0.9.8
- 0.9.9
- 0.9.16-dev
- 1.3.0
- 1.3.1
- 1.3.2
- 1.3.3
- 1.3.4
- 1.3.4-dev
- 1.3.5
- 1.3.6
- 1.3.6-dev
- 1.3.7
- 1.3.8
- 1.3.9
- 1.3.10
- 1.3.11
- 1.3.12
- 1.3.13
- 1.4.0
- 1.4.1
- 1.4.2
- 1.4.3
- 1.4.4
No data.
Red Hat Enterprise Linux 4
apr
Will not fix
Red Hat Enterprise Linux 5
apr
Will not fix
Red Hat Enterprise Linux 6
apr
Will not fix
Red Hat JBoss Enterprise Web Server 1
apr
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 4 | apr | Will not fix | n/a |
| Red Hat Enterprise Linux 5 | apr | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | apr | Will not fix | n/a |
| Red Hat JBoss Enterprise Web Server 1 | apr | Fix deferred | n/a |
No package ranges for this CVE.
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 (19 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 42.14% (0.42138) | 98.65th | v5 (v2026.06.15) |
| Jun 15, 2026 | 43.35% (0.43346) | 98.56th | v5 (v2026.06.15) |
| May 30, 2026 | 40.19% (0.40186) | 97.41th | v4 (v2025.03.14) |
| Oct 11, 2025 | 37.18% (0.37182) | 96.96th | v4 (v2025.03.14) |
| Aug 26, 2025 | 31.95% (0.31946) | 96.66th | v4 (v2025.03.14) |
| Aug 25, 2025 | 26.54% (0.26538) | 96.13th | v4 (v2025.03.14) |
| Jul 13, 2025 | 28.63% (0.28626) | 96.31th | v4 (v2025.03.14) |
| Mar 30, 2025 | 20.84% (0.20840) | 95.13th | v4 (v2025.03.14) |
| Mar 29, 2025 | 23.19% (0.23194) | 93.45th | v4 (v2025.03.14) |
| Mar 17, 2025 | 20.84% (0.20840) | 95.14th | v4 (v2025.03.14) |
| Dec 12, 2024 | 1.17% (0.01171) | 85.63th | v3 (v2023.03.01) |
| May 22, 2024 | 0.83% (0.00828) | 81.96th | v3 (v2023.03.01) |
| Nov 8, 2023 | 0.83% (0.00828) | 79.95th | v3 (v2023.03.01) |
| Sep 10, 2023 | 0.67% (0.00669) | 77.23th | v3 (v2023.03.01) |
| May 6, 2023 | 0.76% (0.00755) | 78.38th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.20% (0.01198) | 82.97th | v3 (v2023.03.01) |
| Mar 6, 2023 | 29.78% (0.29782) | 97.43th | v2 (v2022.01.01) |
| Apr 26, 2022 | 29.78% (0.29782) | 97.30th | v2 (v2022.01.01) |
| Feb 4, 2022 | 30.52% (0.30516) | 96.34th | v2 (v2022.01.01) |
References (14)
- http://mail-archives.apache.org/mod_mbox/apr-commits/201201.mbox/%3C20120115003715.071D423888FD%40eris.apache.org%3E mailing-listx_refsource_MLIST
- http://openwall.com/lists/oss-security/2012/02/08/3 mailing-listx_refsource_MLIST
- http://openwall.com/lists/oss-security/2012/02/09/1 mailing-listx_refsource_MLIST
- http://secunia.com/advisories/47862 third-party-advisoryx_refsource_SECUNIAVendor Advisory
- http://svn.apache.org/viewvc?rev=1231605&view=rev x_refsource_CONFIRMPatch
- http://www.mail-archive.com/dev%40apr.apache.org/msg24439.html mailing-listx_refsource_MLIST
- http://www.mail-archive.com/dev%40apr.apache.org/msg24472.html mailing-listx_refsource_MLIST
- http://www.mail-archive.com/dev%40apr.apache.org/msg24473.html mailing-listx_refsource_MLIST
- http://www.mandriva.com/security/advisories?name=MDVSA-2012:019 vendor-advisoryx_refsource_MANDRIVA
- https://access.redhat.com/security/cve/CVE-2012-0840 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=781606 Issue Tracking
- https://exchange.xforce.ibmcloud.com/vulnerabilities/73096 vdb-entryx_refsource_XF
- https://nvd.nist.gov/vuln/detail/CVE-2012-0840
- https://www.cve.org/CVERecord?id=CVE-2012-0840
Change history (0)
No recorded changes yet.