CVE-2026-31662

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.
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe: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:*:*:*:*:*:*

History

27 Apr 2026, 20:17

Type Values Removed Values Added
CWE CWE-191
CPE cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.15:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
References () https://git.kernel.org/stable/c/1b6f13f626665cac67ba5a012765427680518711 - () https://git.kernel.org/stable/c/1b6f13f626665cac67ba5a012765427680518711 - Patch
References () https://git.kernel.org/stable/c/36ec4fdd6250dcd5e73eb09ea92ed92e9cc28412 - () https://git.kernel.org/stable/c/36ec4fdd6250dcd5e73eb09ea92ed92e9cc28412 - Patch
References () https://git.kernel.org/stable/c/3bcf7aca63f0bcd679ae28e9b99823c608e59ce3 - () https://git.kernel.org/stable/c/3bcf7aca63f0bcd679ae28e9b99823c608e59ce3 - Patch
References () https://git.kernel.org/stable/c/48a5fe38772b6f039522469ee6131a67838221a8 - () https://git.kernel.org/stable/c/48a5fe38772b6f039522469ee6131a67838221a8 - Patch
References () https://git.kernel.org/stable/c/575faea557f1a184a5f09661bd47ebd3ef3769f8 - () https://git.kernel.org/stable/c/575faea557f1a184a5f09661bd47ebd3ef3769f8 - Patch
References () https://git.kernel.org/stable/c/a2ea1ef0167d7a84730638d05c20ccdc421b14b6 - () https://git.kernel.org/stable/c/a2ea1ef0167d7a84730638d05c20ccdc421b14b6 - Patch
References () https://git.kernel.org/stable/c/a7db57ccca21f5801609065473c89a38229ecb92 - () https://git.kernel.org/stable/c/a7db57ccca21f5801609065473c89a38229ecb92 - Patch
References () https://git.kernel.org/stable/c/e0bb732eaf77f9ac2f2638bdac9e39b81e0a9682 - () https://git.kernel.org/stable/c/e0bb732eaf77f9ac2f2638bdac9e39b81e0a9682 - Patch
First Time Linux
Linux linux Kernel

27 Apr 2026, 15:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.5

24 Apr 2026, 15:16

Type Values Removed Values Added
New CVE

Information

Published : 2026-04-24 15:16

Updated : 2026-06-17 10:34


NVD link : CVE-2026-31662

Mitre link : CVE-2026-31662

CVE.ORG link : CVE-2026-31662


JSON object : View

Products Affected

linux

  • linux_kernel
CWE
CWE-191

Integer Underflow (Wrap or Wraparound)