Skip to content
Fencer Vulns
high 7.8

CVE-2021-3345 json

_gcry_md_block_write in cipher/hash-common.c in Libgcrypt version 1.9.0 has a heap-based buffer overflow when the digest final function set…

published 2021-01-29 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26676

cvss
7.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.1%
EPSS 1.1% chance of exploitation in 30 days, percentile 64%
public exploits
0
none known

Summary

_gcry_md_block_write in cipher/hash-common.c in Libgcrypt version 1.9.0 has a heap-based buffer overflow when the digest final function sets a large count value. It is recommended to upgrade to 1.9.1 or later.

Patch / fix

  • libgcrypt openSUSE Tumbleweed 1.9.4-1.2

opensuse advisories openSUSE-SU-2024:10941-1

  • libgcrypt Arch Linux 1.9.1-1

arch linux advisories AVG-1505

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-3345 updated cvss 9.8

libgcrypt: Heap buffer overflow in the block buffer management code

  • Red Hat Enterprise Linux 6 libgcrypt Red Hat Enterprise Linux 7 libgcrypt Red Hat Enterprise Linux 8 libgcrypt Red Hat Enterprise Linux 9 libgcrypt
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.06% chance of exploitation in the next 30 days, higher than 64% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.