CVE-2026-3381
CRITICAL: Perl Compress::Raw::Zlib <=2.219 contains vulnerable zlib; upgrade to 2.220.
Is CVE-2026-3381 being exploited?
Not confirmed. CVE-2026-3381 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.55% probability of exploitation in the next 30 days.
How severe is CVE-2026-3381?
CVE-2026-3381 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-3381?
Yes. A fix has been recorded for CVE-2026-3381. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-3381 affect?
CVE-2026-3381 affects Perl - Compress::Raw::Zlib (<= 2.219). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-3381?
Upgrade to Compress::Raw::Zlib 2.220
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
RCE via crafted decompression input in Perl apps using the module; upgrade to zlib 1.3.2 (2.220) to fix CVE-2026-27171.
Patch when possible
- affected<= 2.219
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.