How severe is CVE-2002-0059?

CVE-2002-0059 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2002-0059 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2002-0059?

CVE-2002-0059 affects Zlib. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2002-0059?

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

When was CVE-2002-0059 published?

CVE-2002-0059 was published on 2002-03-15 and last updated on 2026-06-16.

CVE-2002-0059

CVE-2002-0059 is a critical-severity vulnerability in Zlib with a CVSS 3.x base score of 9.8. 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-415.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-415
Affected product: Zlib
Published: 2002-03-15
Last modified: 2026-06-16

Description

The decompression algorithm in zlib 1.1.3 and earlier, as used in many different utilities and packages, causes inflateEnd to release certain memory more than once (a "double free"), which may allow local and remote attackers to execute arbitrary code via a block of malformed compression data.

Frequently asked questions

What is CVE-2002-0059?: The decompression algorithm in zlib 1.1.3 and earlier, as used in many different utilities and packages, causes inflateEnd to release certain memory more than once (a "double free"), which may allow local and remote attackers to execute arbitrary code via a block of malformed compression data.
How severe is CVE-2002-0059?: CVE-2002-0059 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2002-0059 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2002-0059?: CVE-2002-0059 affects Zlib. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2002-0059?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2002-0059 published?: CVE-2002-0059 was published on 2002-03-15 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*

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