Answer in brief
CVE-2026-53014 records a Medium severity (CVSS 5.5) vulnerability in net/sched: act_mirred: fix wrong device for mac_header_xmit check in tcf_blockcast_redir. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=42f39036cda808d3de243192a2cf5125f12f3047 <8fda5174286119addd28473fb2ec5bdf521c05a8 || >=42f39036cda808d3de243192a2cf5125f12f3047 <7db3e4e03032261b1b519341123fc30d995478ca || >=42f39036cda808d3de243192a2cf5125f12f3047 <4764953c4b47585eb72797b216b63a831dc0c7e6 || >=42f39036cda808d3de243192a2cf5125f12f3047 <4510d140524ca7d6e772db962e013f26f09a63b1 | 8fda5174286119addd28473fb2ec5bdf521c05a8, 7db3e4e03032261b1b519341123fc30d995478ca, 4764953c4b47585eb72797b216b63a831dc0c7e6, 4510d140524ca7d6e772db962e013f26f09a63b1 |
| Linux/Linuxgeneric | 6.8 | Not reported |
Published upstream
Jun 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 24, 2026
In the Linux kernel, the following vulnerability has been resolved: net/sched: act_mirred: fix wrong device for mac_header_xmit check in tcf_blockcast_redir In tcf_blockcast_redir(), when iterating block ports to redirect packets to multiple devices, the mac_header_xmit flag is queried from the wrong device. The loop sends to dev_prev but queries dev_is_mac_header_xmit(dev) — which is the NEXT device in the iteration, not the one being sent to. This causes tcf_mirred_to_dev() to make incorrect decisions about whether to push or pull the MAC header. When the block contains mixed device types (e.g., an ethernet veth and a tunnel device), intermediate devices get the wrong mac_header_xmit flag, leading to skb header corruption. In the worst case, skb_push_rcsum with an incorrect mac_len can exhaust headroom and panic. The last device in the loop is handled correctly (line 365-366 uses dev_is_mac_header_xmit(dev_prev)), confirming this is a copy-paste oversight for the intermediate devices. Fix by using dev_prev instead of dev for the mac_header_xmit query, consistent with the device actually being sent to.
Quoted source text, attributed separately from HOL analysis.