CVE-2026-46281: vmalloc: fix buffer overflow in vrealloc_node_align()
Vulnerability summary
CVE-2026-46281 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.14% chance of exploitation in the next 30 days, higher than 3.4% of scored vulnerabilities.
Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 7 · Related 7Timeline
- 08-06-2026PublishedVulnerability first disclosed.
- 14-06-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: vmalloc: fix buffer overflow in vrealloc_node_align() Commit 4c5d3365882d ("mm/vmalloc: allow to set node and align in vrealloc") added the ability to force a new allocation if the current pointer is on the wrong NUMA node, or if an alignment constraint is not met, even if the user is shrinking the allocation. On this path (need_realloc), the code allocates a new object of 'size' bytes and then memcpy()s 'old_size' bytes into it. If the request is to shrink the object (size < old_size), this results in an out-of-bounds write on the new buffer. Fix this by bounding the copy length by the new allocation size.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.14%
Chance of exploitation in the next 30 days
Percentile
3%
Versus all other CVEs
30-day change
Decrease -0.05 pp
From 0.19% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu99 products
- linux< 7.0.0-27.27
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 7.0.0-1008.8
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 4c5d3365882dbbc0784688784904f440d7a4c0f1, < e9b057a44deff4c59c13f44672a5cc74dcd57522 | ≥ 4c5d3365882dbbc0784688784904f440d7a4c0f1, < b281adf71f786c325eb6d6d1582d4d05313438a8 | ≥ 4c5d3365882dbbc0784688784904f440d7a4c0f1, < 82d1f01292d3f09bf063f829f8ab8de12b4280a1 | 6.18
- linux_kernel≥ 6.18, < 6.18.27 | ≥ 6.19, < 7.0.4 | 7.1:rc1
Debian1 product
- linux< 7.0.4-1
3 vendors · 102 products
