In the Linux kernel, the following vulnerability has been resolved: net/802/mrp: fix vector attribute parsing in mrp_pdu_parse_vecattr In mrp_pdu_parse_vecattr(), vector attribute events are encoded three per byte and valen tracks the number of events left to process. The parser decrements valen after processing the first and second events from each event byte, but not after processing the third one. When valen is exactly a multiple of three, the loop continues after the last valid event and consumes the next byte as a new event byte, applying a spurious event to the MRP applicant state. Additionally, when valen is zero the parser unconditionally consumes attrlen bytes as FirstValue and advances the offset, even though per IEEE 802.1ak a VectorAttribute with only a LeaveAllEvent has valen of zero and no FirstValue or Vector fields. This corrupts the offset for subsequent PDU parsing. Also, when valen exceeds three the loop crosses byte boundaries but the attribute value is not incremented between the last event of one byte and the first event of the next. This causes the first event of the next byte to use the same attribute value as the third event rather than the next consecutive value. Decrement valen after processing the third event, skip FirstValue consumption when valen is zero, and increment the attribute value at the end of each loop iteration.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
| Attack Vector | LOCAL |
|---|---|
| Attack Complexity | LOW |
| Privileges Required | LOW |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | NONE |
| Integrity Impact | NONE |
| Availability Impact | HIGH |
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
NVD-CWE-noinfo
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36b4363c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3853c7880> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd385617340> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd384aa21c0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36b436300> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36b435140> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36a715e40> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd3686c3c00> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd36b4356c0> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd36b437c80> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd310534a40> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd36ad7cb00> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd341bc0480> | Operating System |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* |