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.

Critical 9.8 Published 15 Aug 2026 Updated 17 Aug 2026

An integer overflow in Perl DBI allows heap out-of-bounds writes on 32-bit systems, potentially leading to code execution or crashes.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-73193?

CVE-2026-73193 is a critical vulnerability, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-787, CWE-190

Which versions are affected by CVE-2026-73193?

How do I fix CVE-2026-73193?

Upgrade to a fixed version.

Is CVE-2026-73193 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73193 exists.

Sources

Also known as AZL-96701, DEBIAN-CVE-2026-73193, ECHO-6e5f-914c-dcac, GHSA-wj3v-c3hh-mhqr, MINI-846h-r5xp-v3f5, OESA-2026-3518 and 2 more.