CVE-2026-5089 (GCVE-0-2026-5089)

Vulnerability from cvelistv5 – Published: 2026-05-12 16:14 – Updated: 2026-05-14 13:51
VLAI
Title
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read
Summary
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read. The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer: while ( colon >= ptr && *colon != ':' ) { colon--; } if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-14 13:50 UTC
CWE
  • CWE-124 - Buffer Underwrite ('Buffer Underflow')
Assigner
CPANSec CNA under the redhat root
CNA scorecard C 61/100 over 363 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
TODDR YAML::Syck Affected: 0 , < 1.38 (custom)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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