Answer in brief
CVE-2026-64091 records a Critical severity (CVSS 9.8) vulnerability in batman-adv: tt: fix TOCTOU race for reported vlans. 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 9.8. 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.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:4.17:-:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:4.17:rc7:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* | Not reported | Not reported |
| cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=16116dac23396e73c01eeee97b102e4833a4b205 <e4236bf3ec8d6bb15d0d8d825dcf9933a7d6666b || >=16116dac23396e73c01eeee97b102e4833a4b205 <724a8eb4155669797c96b70d70e354284ae3b5a8 || >=16116dac23396e73c01eeee97b102e4833a4b205 <211ea59988e1cba43cb0367ad65d379b56f9c3bd || >=16116dac23396e73c01eeee97b102e4833a4b205 <65a1e67339aa8c95ac544b796946af388930ee23 || >=16116dac23396e73c01eeee97b102e4833a4b205 <b4d4efd4e351593c81e9293d4b4408d244fa5ee7 || >=16116dac23396e73c01eeee97b102e4833a4b205 <4cc85aec8d3c9ab4dc716dc9f1ed36fca16b227f || >=16116dac23396e73c01eeee97b102e4833a4b205 <9a9c859457bc440a55773e01ff18b1bb5bab6836 || >=16116dac23396e73c01eeee97b102e4833a4b205 <94d27005016be15ffc638b2ecbc4d58805ad7b48 || 3134c5a32810c510f1f447c135cec346acbb71c3 || e861e03a1b5b615ad1b57b1802b17e260eedccfe || 0b81edc8818903c64c4d121bc51cd5825be8cc67 || 90ae6475b1753f0c1a4c66034b5666de3189fac8 || >=3.16.60 <3.17 || >=4.4.217 <4.5 || >=4.9.217 <4.10 || >=4.14.174 <4.15 | e4236bf3ec8d6bb15d0d8d825dcf9933a7d6666b, 724a8eb4155669797c96b70d70e354284ae3b5a8, 211ea59988e1cba43cb0367ad65d379b56f9c3bd, 65a1e67339aa8c95ac544b796946af388930ee23, b4d4efd4e351593c81e9293d4b4408d244fa5ee7, 4cc85aec8d3c9ab4dc716dc9f1ed36fca16b227f, 9a9c859457bc440a55773e01ff18b1bb5bab6836, 94d27005016be15ffc638b2ecbc4d58805ad7b48, 3.17, 4.5, 4.10, 4.15 |
| Linux/Linuxgeneric | 4.17 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: batman-adv: tt: fix TOCTOU race for reported vlans The local TT based TVLV is generated by first checking the number of VLANs which have at least one TT entry. A new buffer with the correct size for the VLANs is then allocated. Only then, the list of VLANs s used to fill the VLAN entries in the buffer. During this time, the meshif_vlan_list_lock is held. But the actual number of TT entries of each VLAN can still increase during this time - just not the number of VLANs in the list. But the prefilter used in the buffer size calculation might still cause an increase of the number of VLANs which need to be stored. Simply because a VLAN might now suddenly have at least one entry when it had none in the pre-alloc check - and then needs to occupy space which was not allocated. It is better to overestimate the buffer size at the beginning and then fill the buffer only with the VLANs which are not empty.
Quoted source text, attributed separately from HOL analysis.