Priority MEDIUM 58
zlib before 1.3.2 allows CPU consumption via crc32_combine64 and crc32_combine_gen64 because x2nmodp can do right shifts within a loop that has no termination condition.
CVSS 3.1MEDIUM 5.5· Local · Low privileges · No interaction · EPSS 0.00248 · Published 2026-02-18 · Partial fix · 1.3.2 CWE-1284
Priority MEDIUM 62
zlib versions up to and including 1.3.1.2 include a global buffer overflow in the untgz utility located under contrib/untgz.
CVSS 4.0MEDIUM 4.6· Local · No auth · User interaction · EPSS 0.00413 · Published 2026-01-07 · Will not fix CWE-787
Priority MEDIUM 49
MiniZip in zlib through 1.3 has an integer overflow and resultant heap-based buffer overflow in zipOpenNewFileInZip4_64 via a long filename, comment, or extra field.
CVSS 3.1CRITICAL 9.8· Network · No auth · No interaction · EPSS 0.03448 · Published 2023-10-14 · Partial fix CWE-190
Priority HIGH 75
zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field.
CVSS 3.1CRITICAL 9.8· Network · No auth · No interaction · EPSS 0.19243 · Published 2022-08-05 · Partial fix CWE-120
Priority HIGH 72
zlib before 1.2.12 allows memory corruption when deflating (i.e., when compressing) if the input has many distant matches.
CVSS 3.1HIGH 7.5· Network · No auth · No interaction · EPSS 0.51733 · Published 2022-03-25 · Fixed in 1.13.4 CWE-787
Priority MEDIUM 51
The crc32_big function in crc32.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact via vectors involving big-endian CRC calculation.
CVSS 3.1CRITICAL 9.8· Network · No auth · No interaction · EPSS 0.05766 · Published 2017-05-23 · Fixed
Priority MEDIUM 48
The inflateMark function in inflate.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact via vectors involving left shifts of negative integers.
CVSS 3.1HIGH 8.8· Network · No auth · User interaction · EPSS 0.05204 · Published 2017-05-23 · Fixed CWE-1335
Priority MEDIUM 59
inffast.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic.
CVSS 3.1CRITICAL 9.8· Network · No auth · No interaction · EPSS 0.0755 · Published 2017-05-23 · Fixed
Priority MEDIUM 48
inftrees.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic.
CVSS 3.1HIGH 8.8· Network · No auth · User interaction · EPSS 0.04875 · Published 2017-05-23 · Fixed
Priority LOW 30
inftrees.h in zlib 1.2.2 allows remote attackers to cause a denial of service (application crash) via an invalid file that causes a large dynamic tree to be produced.
CVSS 2.0MEDIUM 5.0· Network · No auth · Interaction — · EPSS 0.04076 · Published 2005-07-26 · Fixed
Priority MEDIUM 41
zlib 1.2 and later versions allows remote attackers to cause a denial of service (crash) via a crafted compressed stream with an incomplete code description of a length greater than 1, which leads to a buffer overflow, a…
CVSS 2.0HIGH 7.5· Network · No auth · Interaction — · EPSS 0.05627 · Published 2005-07-06 · Fixed
Priority LOW 12
The error handling in the (1) inflate and (2) inflateBack functions in ZLib compression library 1.2.x allows local users to cause a denial of service (application crash).
CVSS 2.0LOW 2.1· Local · No auth · Interaction — · EPSS 0.00472 · Published 2004-09-14 · No fix listed
Priority MEDIUM 54
Buffer overflow in the gzprintf function in zlib 1.1.4, when zlib is compiled without vsnprintf or when long inputs are truncated using vsnprintf, allows attackers to cause a denial of service or possibly execute arbitra…
CVSS 2.0HIGH 7.5· Network · No auth · Interaction — · EPSS 0.25987 · Published 2004-09-01 · Fixed
Priority MEDIUM 54
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 atta…
CVSS 3.1CRITICAL 9.8· Network · No auth · No interaction · EPSS 0.09691 · Published 2002-06-25 · Fixed CWE-415