rxrpc: Fix the ACK parser to extract the SACK table for parsing

Summary

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix the ACK parser to extract the SACK table for parsing Fix modification of the received skbuff in rxrpc_input_soft_acks() and a potential incorrect access of the buffer in a fragmented UDP packet (the packet would probably have to be deliberately pre-generated as fragmented) when AF_RXRPC tries to extract the contents of the SACK table by copying out the contents of the SACK table into a buffer before attempting to parse AF_RXRPC assumes that it can just call skb_condense() and then validly access the SACK table from skb->data and that it will be a flat buffer - but skb_condense() can silently fail to do anything under some circumstances. Note that whilst rxrpc_input_soft_acks() should be able to parse extended ACKs, the rest of AF_RXRPC doesn't currently support that. Further, there's then no need to call skb_condense() in rxrpc_input_ack(), so don't.

Timeline

1. Jun 25, 2026, 8:38 AM UTCCVE published
2. Oct 16, 2026, 3:26 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Oct 19, 2026, 7:57 PM UTCRecord last updated

Affected versions

• Linux Linux

  From d57a3a151660902091491ac2633134e1be92557f · fixed in 5d1ae4e17a3ecd8561cdb4f4f70152f41039c4e1; From d57a3a151660902091491ac2633134e1be92557f · fixed in 775c5e89272a2615b72bb84f611ba66fa3b7493e; From d57a3a151660902091491ac2633134e1be92557f · fixed in 566c4c1244de50fbff1f89ff93c9d7b0fc256db4; From d57a3a151660902091491ac2633134e1be92557f · fixed in 224298450be5c04d2a6ea1c2a94669d7ebf65d00; From d57a3a151660902091491ac2633134e1be92557f · fixed in 333b6d5bb9f87827ac2639c737bf9613dbae7253

• Linux Linux

  6.2

• KernelLinux

  From 6.2.0 · fixed in 6.6.144; From 6.7.0 · fixed in 6.12.95; From 6.13.0 · fixed in 6.18.36; From 6.19.0 · fixed in 7.0.13

References 5