CVE catalog

CVE-2016-6354

flex: CVE-2016-6354

Severity: Critical · CVSS 9.8CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: Jul 18, 2016, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 9.12% · Oct 27, 2026

Heap-based buffer overflow in the yy_get_next_buffer function in Flex before 2.6.1 might allow context-dependent attackers to cause a denial of service or possibly execute arbitrary code via vectors involving num_to_read.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	flex	sid	`2.6.4-8.2`	fixed
Debian	flex	forky	`2.6.4-8.2`	fixed
Debian	flex	trixie	`2.6.4-8.2`	fixed
Debian	flex	bookworm	`2.6.4-8.2`	fixed
Alpine	flex	3.2	`2.5.39-r1`	fixed
Alpine	flex	3.3	`2.5.39-r3`	fixed
Alpine	flex	3.4	`2.6.1-r0`	fixed
Ubuntu	flex	16.04	`2.5.39-8`	vulnerable
Ubuntu	flex	16.04	`2.6.0-1`	vulnerable
Ubuntu	flex	16.04	`2.6.0-3`	vulnerable
Ubuntu	flex	16.04	`2.6.0-4`	vulnerable
Ubuntu	flex	16.04	`2.6.0-6`	vulnerable
Ubuntu	flex	16.04	`2.6.0-7`	vulnerable
Ubuntu	flex	16.04	`2.6.0-8`	vulnerable
Ubuntu	flex	16.04	`2.6.0-9`	vulnerable
Ubuntu	flex	16.04	`2.6.0-11`	vulnerable
Suse	wireshark	linux enterprise desktop 12 sp1	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise desktop 12 sp2	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise server for raspberry pi 12 sp2	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise software development kit 12 sp1	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise software development kit 12 sp2	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise server 12 sp1	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise server for sap applications 12 sp1	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise server 12 sp2	`2.2.6-44.3`	fixed
Suse	wireshark	linux enterprise server for sap applications 12 sp2	`2.2.6-44.3`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	flex	source	sid	`2.6.1-1`	not yet assigned	Not reported	[832768]
Debian	flex	source	forky	`2.6.1-1`	not yet assigned	Not reported	[832768]
Debian	flex	source	trixie	`2.6.1-1`	not yet assigned	Not reported	[832768]
Debian	flex	source	bookworm	`2.6.1-1`	not yet assigned	Not reported	[832768]
Alpine	flex	apk	3.2	`2.5.39-r1`	Not reported	ALPINE-CVE-2016-6354	Not reported
Alpine	flex	apk	3.3	`2.5.39-r3`	Not reported	ALPINE-CVE-2016-6354	Not reported
Alpine	flex	apk	3.4	`2.6.1-r0`	Not reported	ALPINE-CVE-2016-6354	Not reported
Suse	wireshark	rpm	linux enterprise desktop 12 sp1	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise desktop 12 sp2	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise server for raspberry pi 12 sp2	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise software development kit 12 sp1	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise software development kit 12 sp2	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise server 12 sp1	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise server for sap applications 12 sp1	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise server 12 sp2	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported
Suse	wireshark	rpm	linux enterprise server for sap applications 12 sp2	`2.2.6-44.3`	Not reported	SUSE-SU-2017:1442-1	Not reported

[Debian bug #832768]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[flex]Unknown
Details (2)
- 2.6.4-8.2 · amd64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
- 2.6.4-8.2 · arm64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
[flex-doc]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2 · all · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
- 2.6.4-8.2 · all · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
[libfl2]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2 · amd64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
- 2.6.4-8.2 · arm64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
[libfl-dev]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2 · amd64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12
- 2.6.4-8.2 · arm64 · bookworm
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · bookworm; dsa · flex · debian · 12

[Debian 13 (Trixie)]

[flex]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2+b4 · amd64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
- 2.6.4-8.2+b4 · arm64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
[flex-doc]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2 · all · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
- 2.6.4-8.2 · all · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
[libfl2]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2+b4 · amd64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
- 2.6.4-8.2+b4 · arm64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
[libfl-dev]Unknown
Source package: [flex]
Details (2)
- 2.6.4-8.2+b4 · amd64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13
- 2.6.4-8.2+b4 · arm64 · trixie
  Fixed · Fixed: 2.6.1-1
  dsa · flex · debian · 13

Observed: Oct 23, 2026, 5:22:38 PM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]