Vulnerability · CVE-2016-9843
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.
Published May 23, 2017 · catalog updated Jun 17, 2026 · The crc32_big function in
Last checked Nov 4, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2016-9843. EPSS is 5.77%. Act only if a listed version of The crc32_big function in is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (The crc32_big function in).
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2026-27820 · Critical
- CVE-2023-45853 · Critical
- CVE-2022-37434 · Critical
- Severity
- Critical9.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 5.77%
- Remediation
- Version ranges on file
- Affected products
- cpe canonical/ubuntu linux · cpe debian/debian linux · cpe opensuse/leap · cpe opensuse/opensuse · cpe zlib/zlib
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe canonical/ubuntu linux16.04
- cpe debian/debian linux8.0
- cpe opensuse/leap42.1
- cpe opensuse/leap42.2
- cpe opensuse/opensuse13.2
- cpe zlib/zlib< 1.2.9
How to fix CVE-2016-9843
Upgrade
CVE-2016-9843 lists a fix boundary at 1.2.9. Compare the installed build with that boundary before you change production.
Version check
Affected < 1.2.9
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2016-9843. EPSS is 5.77%. Act only if a listed version of The crc32_big function in is installed.
Which versions are affected?
Compare what you have installed with canonical/ubuntu linux 16.04; debian/debian linux 8.0. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 5.77%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 23, 2017 · Monitored products — high
Detected
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.
Jun 17, 2026 · Monitored products — high
Updated
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.
Sources
- CVE.orgVulnerability recordCVE-2016-9843
Official CVE identifier
cve.org - Monitored products — highVendor advisoryCVE-2016-9843
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.
nvd.nist.gov - Shodan InternetDBThreat intelligenceCVE-2016-9843internetdb.shodan.io
References
Freshness
Last verified in this catalog Nov 4, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- Shodan InternetDBNov 3, 2026
- CVE.orgNov 2, 2026
- Monitored products — highNov 1, 2026