How severe is CVE-2008-1721?

CVE-2008-1721 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2008-1721 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2008-1721?

CVE-2008-1721 primarily affects Python. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2008-1721?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2008-1721 published?

CVE-2008-1721 was published on 2008-04-10 and last updated on 2026-06-16.

CVE-2008-1721

CVE-2008-1721 is a high-severity vulnerability in Python with a CVSS 2.0 base score of 7.5. Its EPSS exploit-prediction score of 23% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-681.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 23% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-681
Affected product: Python
Published: 2008-04-10
Last modified: 2026-06-16

Description

Integer signedness error in the zlib extension module in Python 2.5.2 and earlier allows remote attackers to execute arbitrary code via a negative signed integer, which triggers insufficient memory allocation and a buffer overflow.

Frequently asked questions

What is CVE-2008-1721?: Integer signedness error in the zlib extension module in Python 2.5.2 and earlier allows remote attackers to execute arbitrary code via a negative signed integer, which triggers insufficient memory allocation and a buffer overflow.
How severe is CVE-2008-1721?: CVE-2008-1721 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2008-1721 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 23% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2008-1721?: CVE-2008-1721 primarily affects Python. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2008-1721?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2008-1721 published?: CVE-2008-1721 was published on 2008-04-10 and last updated on 2026-06-16.

References

Affected products (6)

cpe:2.3:a:python:python:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:4.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:6.06:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:7.04:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:7.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:8.04:*:*:*:-:*:*:*

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