CVE-2023-31484: Improper Certificate Validation
Source CVE Database V5
Not known to be exploited · CVSS 8.1 High · fixed in 2.35 : patch affected systems soon.
Data as of 26 Oct 2026, 09:15 UTC
- EPSS
- 1.5% chance of exploitation in 30 days – higher than 74% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.35
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 Apr 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
1. Upgrade CPAN.pm to version 2.35 or later as soon as it becomes available to ensure proper TLS certificate validation. 2. In the interim, configure network security controls such as TLS interception detection, strict firewall rules, and network segmentation to limit exposure to MITM attacks. 3. Employ endpoint security solutions that monitor and verify the integrity of downloaded Perl modules and alert on suspicious changes. 4. Use alternative secure package management tools or mirrors that enforce certificate validation if upgrading CPAN.pm is not immediately feasible. 5. Educate developers and system administrators about the risks of unverified TLS connections and encourage best practices for secure software supply chain management. 6. Regularly audit Perl environments and dependencies for signs of tampering or unauthorized modifications. 7. Implement network-level protections such as DNSSEC and HTTP Strict Transport Security (HSTS) where applicable to reduce MITM risks.
Description
CPAN.pm before 2.35 does not verify TLS certificates when downloading distributions over HTTPS.
References
- blog.hackeriet.no/perl-http-tiny-insecure-tls-default-affects-cpan-modules/ (opens in a new tab)
- openwall.com/lists/oss-security/2023/04/18/14 (opens in a new tab)
- github.com/andk/cpanpm/pull/175 (opens in a new tab)
- metacpan.org/dist/CPAN/changes (opens in a new tab)
- openwall.com/lists/oss-security/2023/04/29/1 (opens in a new tab)
- openwall.com/lists/oss-security/2023/05/03/3 (opens in a new tab)
- openwall.com/lists/oss-security/2023/05/03/5 (opens in a new tab)
- openwall.com/lists/oss-security/2023/05/07/2 (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BM6UW55CNFUTNGD5ZRKGUKKKFDJGMFHL/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LEGCEOKFJVBJ2QQ6S2H4NAEWTUERC7SB/ (opens in a new tab)
- security.netapp.com/advisory/ntap-20240621-0007/ (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/10/msg00017.html (opens in a new tab)