CVE-2026-64381: linux Out-of-bounds Write
Vulnerability summary
CVE-2026-64381 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.3% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 32 · Related 32Timeline
- 25-07-2026PublishedVulnerability first disclosed.
- 17-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix next buffer leak in receive_encrypted_standard() receive_encrypted_standard() allocates next_buffer before checking whether the number of compound PDUs already reached MAX_COMPOUND. If the limit check fails, the function returns immediately and the newly allocated next_buffer is not assigned to server->smallbuf/server->bigbuf, making it leaked. Move the MAX_COMPOUND check before allocating next_buffer.
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
0.13%
Chance of exploitation in the next 30 days
Percentile
2%
Versus all other CVEs
30-day change
0.00 pp
From 0.13% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu165 products
- linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-147.147 | < 7.0.0-31.31
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1067.70 | < 7.0.0-1012.12
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian2 products
- linux< 6.1.180-1 | < 6.12.96-1 | < 7.1.4-1
- linux-6.12< 6.12.100-1~deb12u1
Linux2 products
- linux≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 94e4f672db029414b9888b5137a7559f1febf2d8 | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 68fc0b6cc03ca58060c0f36454e169f5fe258974 | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 07e0ab81df1790afa35732a4e8e07ff831b29008 | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 9136a08dc29328edd9867f2545e73906ac9df93b | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 67097772df7791c53d608f04bd31c676ccf79b83 | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 297243e365fc9fe2f8e9b7dd535a65d922cd108b | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 927d4805aea0a287d36dd4f826ee24d69a2afee3 | ≥ b24df3e30cbf48255db866720fb71f14bf9d2f39, < 1c6267a1d5cf4c73b656f8181b310cbbb3e4767b | 4.19
- linux_kernel≥ 4.19, < 5.10.261 | ≥ 5.11, < 5.15.212 | ≥ 5.16, < 6.1.178 | ≥ 6.2, < 6.6.145 | ≥ 6.7, < 6.12.96 | ≥ 6.13, < 6.18.39 | ≥ 6.19, < 7.1.4
3 vendors · 169 products
