Open5GS BSF context.c bsf_sess_find_by_ipv6prefix denial of service

published 2026-05-01 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-26661

cvss: 4.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits: 0; none known

A flaw has been found in Open5GS up to 2.7.7. This issue affects the function bsf_sess_find_by_ipv6prefix of the file /src/bsf/context.c of the component BSF. This manipulation of the argument ipv6Prefix causes denial of service. It is possible to initiate the attack remotely. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 6 mo ago (2026-05-01)

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/open5gs/open5gs/issues/4401 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
CNA	3.0	4.3	CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:ND/RC:UR
CNA	4.0	2.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CNA	3.1	4.3	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CNA	2.0	4.0	AV:N/AC:L/Au:S/C:N/I:N/A:P

Affected products

n/a Open5GS

Classification

Weakness

CWE-404 Improper Resource Shutdown or Release

References

github.com /open5gs/open5gs/issues/4401
exploit, issue-tracking
vuldb.com /vuln/360530
vdb-entry, technical-description
vuldb.com /vuln/360530/cti
signature, permissions-required
vuldb.com /submit/804322
third-party-advisory
github.com /open5gs/open5gs/
product

Sources

CVE List CVE-2026-7583
NVD CVE-2026-7583

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.

Summary