Answer in brief
CVE-2026-45890 records a Medium severity (CVSS 5.5) vulnerability in xen-netback: reject zero-queue configuration from guest. 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.
Answer in brief
CVE-2026-45890 records a Medium severity (CVSS 5.5) vulnerability in xen-netback: reject zero-queue configuration from guest. 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 | >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <2993e0f904c45f8af12917344bb1cac7ccd05a60 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <787bfa423228c4b02ba3368128f625d579085353 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <ce66d6786de45b7ed9cbbdc0988054bf09e58f54 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <88b0fced1bbbfdb356a007592604008ffc93a6a1 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <ec4859ac5c933e3315543a61adc1ca4358006a41 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <654780dee9eae419e1648ea58462c4efe54518fa || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <d99f69ddc70fd9f4b8148add62209a1a8eb5c615 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <6d1dc8014334c7fb25719999bca84d811e60a559 | 2993e0f904c45f8af12917344bb1cac7ccd05a60, 787bfa423228c4b02ba3368128f625d579085353, ce66d6786de45b7ed9cbbdc0988054bf09e58f54, 88b0fced1bbbfdb356a007592604008ffc93a6a1, ec4859ac5c933e3315543a61adc1ca4358006a41, 654780dee9eae419e1648ea58462c4efe54518fa, d99f69ddc70fd9f4b8148add62209a1a8eb5c615, 6d1dc8014334c7fb25719999bca84d811e60a559 |
| Linux/Linuxgeneric | 3.16 | Not reported |
Published upstream
May 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
In the Linux kernel, the following vulnerability has been resolved: xen-netback: reject zero-queue configuration from guest A malicious or buggy Xen guest can write "0" to the xenbus key "multi-queue-num-queues". The connect() function in the backend only validates the upper bound (requested_num_queues > xenvif_max_queues) but not zero, allowing requested_num_queues=0 to reach vzalloc(array_size(0, sizeof(struct xenvif_queue))), which triggers WARN_ON_ONCE(!size) in __vmalloc_node_range(). On systems with panic_on_warn=1, this allows a guest-to-host denial of service. The Xen network interface specification requires the queue count to be "greater than zero". Add a zero check to match the validation already present in xen-blkback, which has included this guard since its multi-queue support was added.
Quoted source text, attributed separately from HOL analysis.
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 | >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <2993e0f904c45f8af12917344bb1cac7ccd05a60 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <787bfa423228c4b02ba3368128f625d579085353 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <ce66d6786de45b7ed9cbbdc0988054bf09e58f54 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <88b0fced1bbbfdb356a007592604008ffc93a6a1 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <ec4859ac5c933e3315543a61adc1ca4358006a41 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <654780dee9eae419e1648ea58462c4efe54518fa || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <d99f69ddc70fd9f4b8148add62209a1a8eb5c615 || >=8d3d53b3e43363e79ab9a9ecc149b06c1314b25d <6d1dc8014334c7fb25719999bca84d811e60a559 | 2993e0f904c45f8af12917344bb1cac7ccd05a60, 787bfa423228c4b02ba3368128f625d579085353, ce66d6786de45b7ed9cbbdc0988054bf09e58f54, 88b0fced1bbbfdb356a007592604008ffc93a6a1, ec4859ac5c933e3315543a61adc1ca4358006a41, 654780dee9eae419e1648ea58462c4efe54518fa, d99f69ddc70fd9f4b8148add62209a1a8eb5c615, 6d1dc8014334c7fb25719999bca84d811e60a559 |
| Linux/Linuxgeneric | 3.16 | Not reported |
Published upstream
May 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
In the Linux kernel, the following vulnerability has been resolved: xen-netback: reject zero-queue configuration from guest A malicious or buggy Xen guest can write "0" to the xenbus key "multi-queue-num-queues". The connect() function in the backend only validates the upper bound (requested_num_queues > xenvif_max_queues) but not zero, allowing requested_num_queues=0 to reach vzalloc(array_size(0, sizeof(struct xenvif_queue))), which triggers WARN_ON_ONCE(!size) in __vmalloc_node_range(). On systems with panic_on_warn=1, this allows a guest-to-host denial of service. The Xen network interface specification requires the queue count to be "greater than zero". Add a zero check to match the validation already present in xen-blkback, which has included this guard since its multi-queue support was added.
Quoted source text, attributed separately from HOL analysis.