CVE-2026-8796 Sereal::Decoder versions before 5.005 for Perl allow heap out-of-bounds read via crafted input
A heap out-of-bounds read in the Perl Sereal::Decoder library allows attackers to read sensitive memory or cause crashes via crafted input.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-8796?
CVE-2026-8796 is a high-severity memory corruption vulnerability in YVES Sereal::Decoder, published on 31 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Sereal::Decoder versions before 5.005 for Perl allow heap out-of-bounds read via crafted input.
In Perl/Decoder/srl_decoder.c, srl_read_object() and srl_read_hash() process a COPY tag, a back-reference whose target byte the decoder re-decodes as a fresh tag. When that target byte matches the SHORT_BINARY pattern (an inline string whose length is encoded in the low bits of the tag), the resulting read is not bounded to precede the COPY tag's own offset and can run past the end of the input buffer. An attacker controlled COPY offset can land inside a previously decoded value rather than on a tag boundary, planting a byte that the decoder reads as a SHORT_BINARY tag and consuming up to 31 following bytes from the heap as a class name (OBJECT path) or hash key (HASH path).
Weakness: CWE-125
Which versions are affected by CVE-2026-8796?
Linux distribution packages (1)
perl-Sereal-Decoder openSUSE:Tumbleweed | All versions | 5.6.0-1.1 |
How do I fix CVE-2026-8796?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-8796 being exploited?
There is no known exploitation of CVE-2026-8796 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-8796, GHSA-xhpj-269v-vq2q, UBUNTU-CVE-2026-8796, openSUSE-SU-2026:10924-1.