DEBIAN-CVE-2026-49943

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Source
https://security-tracker.debian.org/tracker/CVE-2026-49943
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-49943
Upstream
Published
2026-06-02T17:16:37Z
Modified
2026-09-14T17:03:17Z
Severity
  • 6.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

CZ.NIC BIRD Internet Routing Daemon through 2.19.0 contains a stack-based buffer overflow in the BGP AS_PATH mask matching implementation in nest/a-path.c. The as_path_match() function uses a fixed-size stack array of 2048 + 1 pm_pos entries, while parse_path() expands AS_PATH segments from a received BGP UPDATE without enforcing a corresponding capacity limit. When RFC 8654 BGP Extended Messages are enabled and a BIRD filter evaluates an AS path mask expression such as "bgp_path ~ [= ... =]", an established BGP peer can send a long AS_PATH containing more than 2048 expanded ASNs. This causes parse_path()/as_path_match() to write beyond the fixed stack buffer, resulting in a crash of the daemon. NOTE: reportedly, the Supplier's position is that a fix is not being prioritized because all network operators should already be rejecting routes with unusually long attributes.

References

Affected packages

Debian:12
bird

Package

Name
bird
Purl
pkg:deb/debian/bird?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.6.8-2.1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"
bird2

Package

Name
bird2
Purl
pkg:deb/debian/bird2?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.0.12-7
2.14-1
2.15-1
2.15.1-1
2.15.1-1.1
2.16-1
2.16.1-1
2.17-1
2.17.1-1
2.17.2-1
2.17.3-1
2.17.3-2
2.18-1
2.18.1-1
2.19.0-1
2.19.1-1
2.19.2-1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"
Debian:13
bird2

Package

Name
bird2
Purl
pkg:deb/debian/bird2?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.17.1-1
2.17.1-1+deb13u1
2.17.1-1+deb13u2
2.17.2-1
2.17.3-1
2.17.3-2
2.17.5-0+deb13u1
2.18-1
2.18.1-1
2.19.0-1
2.19.1-1
2.19.2-1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"
bird3

Package

Name
bird3
Purl
pkg:deb/debian/bird3?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

3.*
3.1.0-1
3.1.4-1
3.1.5-1
3.1.5-2
3.1.7-0+deb13u1
3.2.0-1
3.2.1-1
3.3.0-1~bpo13+1
3.3.0-1
3.3.1-1
3.3.2-1~bpo13+1
3.3.2-1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"
Debian:14
bird2

Package

Name
bird2
Purl
pkg:deb/debian/bird2?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

2.*
2.17.1-1
2.17.2-1
2.17.3-1
2.17.3-2
2.18-1
2.18.1-1
2.19.0-1
2.19.1-1
2.19.2-1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"
bird3

Package

Name
bird3
Purl
pkg:deb/debian/bird3?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

3.*
3.1.0-1
3.1.4-1
3.1.5-1
3.1.5-2
3.2.0-1
3.2.1-1
3.3.0-1~bpo13+1
3.3.0-1
3.3.1-1
3.3.2-1~bpo13+1
3.3.2-1

Ecosystem specific 

{
    "urgency":  "unimportant"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-49943.json"