tipc: fix bc_ackers underflow on duplicate GRP_ACK_MSG (Linux Linux)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.39 % · percentile 33 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- Linux
- NVD status
- Modified
Description
In the Linux kernel, the following vulnerability has been resolved: tipc: fix bc_ackers underflow on duplicate GRP_ACK_MSG The GRP_ACK_MSG handler in tipc_group_proto_rcv() currently decrements bc_ackers on every inbound group ACK, even when the same member has already acknowledged the current broadcast round. Because bc_ackers is a u16, a duplicate ACK received after the last legitimate ACK wraps the counter to 65535. Once wrapped, tipc_group_bc_cong() keeps reporting congestion and later group broadcasts on the affected socket stay blocked until the group is recreated. Fix this by ignoring duplicate or stale ACKs before touching bc_acked or bc_ackers. This makes repeated GRP_ACK_MSG handling idempotent and prevents the underflow path.
Weaknesses (CWE)
References
- https://git.kernel.org/stable/c/a7db57ccca21f5801609065473c89a38229ecb92
- https://git.kernel.org/stable/c/36ec4fdd6250dcd5e73eb09ea92ed92e9cc28412
- https://git.kernel.org/stable/c/575faea557f1a184a5f09661bd47ebd3ef3769f8
- https://git.kernel.org/stable/c/3bcf7aca63f0bcd679ae28e9b99823c608e59ce3
- https://git.kernel.org/stable/c/a2ea1ef0167d7a84730638d05c20ccdc421b14b6
- https://git.kernel.org/stable/c/1b6f13f626665cac67ba5a012765427680518711
- https://git.kernel.org/stable/c/e0bb732eaf77f9ac2f2638bdac9e39b81e0a9682
- https://git.kernel.org/stable/c/48a5fe38772b6f039522469ee6131a67838221a8
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | Linux |
| CVSS 3.1 | HIGH 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | NVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary) |
European references
- ENISA EUVD · EUVD-2026-25555
- GCVE · GCVE-0-2026-31662
CERT-FR advisories
- CERTFR-2026-AVI-1229 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1093 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-1066 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0985 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0954 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0926 — Multiples vulnérabilités dans le noyau Linux d'Ubuntu · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0697 — Multiples vulnérabilités dans le noyau Linux de SUSE · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0696 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0548 — Multiples vulnérabilités dans le noyau Linux de Debian · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0547 — Multiples vulnérabilités dans le noyau Linux de Debian LTS · cert.ssi.gouv.fr
- CERTFR-2026-AVI-0526 — Multiples vulnérabilités dans les produits Microsoft · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 4.15.1 < 5.10.253cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.11 < 5.15.203cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 5.16 < 6.1.169cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.2 < 6.6.135cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.7 < 6.12.82cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.13 < 6.18.23cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*≥ 6.19 < 6.19.13cpe:2.3:o:linux:linux_kernel:4.15:-:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| Linux · Linux | affected 2f487712b89376fce267223bbb0db93d393d4b09 < a7db57ccca21f5801609065473c89a38229ecb92 ; affected 2f487712b89376fce267223bbb0db93d393d4b09 < 36ec4fdd6250dcd5e73eb09ea92ed92e9cc28412 ; affected 2f487712b89376fce267223bbb0db93d393d4b09 < 575faea557f1a184a5f09661bd47ebd3ef3769f8 ; affected 2f487712b89376fce267223bbb0db93d393d4b09 < 3bcf7aca63f0bcd679ae28e9b99823c608e59ce3 ; affected 2f487712b89376fce267223bbb0db93d393d4b09 < a2ea1ef0167d7a84730638d05c20ccdc421b14b6 ; affected 2f487712b89376fce267223bbb0db93d393d4b09 < 1b6f13f626665cac67ba5a012765427680518711 |
| Linux · Linux | affected 4.15 ; unaffected 0 < 4.15 ; unaffected 5.10.253 ≤ 5.10.* ; unaffected 5.15.203 ≤ 5.15.* ; unaffected 6.1.169 ≤ 6.1.* ; unaffected 6.6.135 ≤ 6.6.* |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |