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Fencer Vulns
high 7.5

CVE-2021-27799 json

ean_leading_zeroes in backend/upcean.c in Zint Barcode Generator 2.9.1 has a stack-based buffer overflow that is reachable from the C API t…

published 2021-02-26 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-14540

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
2.4%
EPSS 2.4% chance of exploitation in 30 days, percentile 83%
public exploits
0
none known

Summary

ean_leading_zeroes in backend/upcean.c in Zint Barcode Generator 2.9.1 has a stack-based buffer overflow that is reachable from the C API through an application that includes the Zint Barcode Generator library code.

Patch / fix

  • zint Debian 14, Debian 13, Debian 12 2.9.1-1.1

debian advisories DEBIAN-CVE-2021-27799

  • zint Arch Linux 2.9.1-2

arch linux advisories AVG-1625

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-2021-27799 updated cvss 9.8

zint: stack-based buffer overflow

  • Red Hat All currently supported Red Hat products
    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

2.37% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • sourceforge.net https://sourceforge.net/p/zint/tickets/218/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

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.