How severe is CVE-2012-0840?

CVE-2012-0840 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2012-0840 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 43% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-0840?

CVE-2012-0840 primarily affects Apache Portable Runtime. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-0840?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2012-0840 published?

CVE-2012-0840 was published on 2012-02-10 and last updated on 2026-06-16.

CVE-2012-0840

CVE-2012-0840 is a medium-severity vulnerability in Apache Portable Runtime with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 43% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 43% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Portable Runtime
Published: 2012-02-10
Last modified: 2026-06-16

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.

Frequently asked questions

What is CVE-2012-0840?: 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.
How severe is CVE-2012-0840?: CVE-2012-0840 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2012-0840 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 43% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-0840?: CVE-2012-0840 primarily affects Apache Portable Runtime. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-0840?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-0840 published?: CVE-2012-0840 was published on 2012-02-10 and last updated on 2026-06-16.

References

Affected products (35)

cpe:2.3:a:apache:portable_runtime:*:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.2-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.3-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.4:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.5:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.6:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.7:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.7-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.8:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.9:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:0.9.16-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.4:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.4-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.5:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.6:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.6-dev:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.7:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.8:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.9:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.10:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.11:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.12:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.3.13:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.4.0:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.4.1:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.4.2:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.4.3:*:*:*:*:*:*:*
cpe:2.3:a:apache:portable_runtime:1.4.4:*:*:*:*:*:*:*

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