CVE-2026-73193

CVE-2026-73193 is a critical-severity vulnerability with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-190.

Key facts

Description

DBI versions before 1.652 for Perl allow a heap out-of-bounds write on 32-bit perl via an integer wraparound in the output buffer size computed by preparse. preparse reserves its output buffer with `newSV(strlen(statement) * 7 + 16)`, budgeting seven output bytes per input byte for the longest ':p99999' expansion. The product is computed in STRLEN, which is 32 bits wide on a 32-bit perl build, so a statement of 613,566,757 bytes multiplies to 4,294,967,299, wraps modulo 2^32 to 3, and reserves 19 bytes. The parser then copies the statement out through a raw pointer with no capacity check, writing the whole 585 MB input past the end of the allocation. The 99,999 placeholder limit does not bound this path, which is reached by ordinary non-placeholder content. Any caller that passes an untrusted statement of that length to preparse on a 32-bit perl gets a heap out-of-bounds write of attacker controlled bytes. Builds with a 64-bit STRLEN are not affected, since the wrap there needs a statement of about 2.3 exabytes.

Frequently asked questions

What is CVE-2026-73193?
DBI versions before 1.652 for Perl allow a heap out-of-bounds write on 32-bit perl via an integer wraparound in the output buffer size computed by preparse. preparse reserves its output buffer with `newSV(strlen(statement) * 7 + 16)`, budgeting seven output bytes per input byte for the longest ':p99999' expansion. The product is computed in STRLEN, which is 32 bits wide on a 32-bit perl build, so a statement of 613,566,757 bytes multiplies to 4,294,967,299, wraps modulo 2^32 to 3, and reserves 19 bytes. The parser then copies the statement out through a raw pointer with no capacity check, writing the whole 585 MB input past the end of the allocation. The 99,999 placeholder limit does not bound this path, which is reached by ordinary non-placeholder content. Any caller that passes an untrusted statement of that length to preparse on a 32-bit perl gets a heap out-of-bounds write of attacker controlled bytes. Builds with a 64-bit STRLEN are not affected, since the wrap there needs a statement of about 2.3 exabytes.
How severe is CVE-2026-73193?
CVE-2026-73193 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-73193 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-73193?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-73193 published?
CVE-2026-73193 was published on 2026-08-15 and last updated on 2026-08-17.

References

Other CWE-190 (Integer Overflow or Wraparound) vulnerabilities

Browse all CWE-190 (Integer Overflow or Wraparound) vulnerabilities →