How severe is CVE-2012-6123?

CVE-2012-6123 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2012-6123 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2012-6123?

CVE-2012-6123 primarily affects Call-cc Chicken. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2012-6123?

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

When was CVE-2012-6123 published?

CVE-2012-6123 was published on 2019-10-31 and last updated on 2026-06-16.

CVE-2012-6123

CVE-2012-6123 is a medium-severity vulnerability in Call-cc Chicken with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Call-cc Chicken
Published: 2019-10-31
Last modified: 2026-06-16

Description

Chicken before 4.8.0 does not properly handle NUL bytes in certain strings, which allows an attacker to conduct "poisoned NUL byte attack."

Frequently asked questions

What is CVE-2012-6123?: Chicken before 4.8.0 does not properly handle NUL bytes in certain strings, which allows an attacker to conduct "poisoned NUL byte attack."
How severe is CVE-2012-6123?: CVE-2012-6123 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2012-6123 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-6123?: CVE-2012-6123 primarily affects Call-cc Chicken. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-6123?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-6123 published?: CVE-2012-6123 was published on 2019-10-31 and last updated on 2026-06-16.

References

Affected products (4)

cpe:2.3:a:call-cc:chicken:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

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