CVE-2023-52775: net/smc: avoid data corruption caused by decline
Vulnerability summary
CVE-2023-52775 is a high (CVSS 8.2) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.67% chance of exploitation in the next 30 days, higher than 52% of scored vulnerabilities.
Severe, CVSS 8.2 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 11 · Related 8Timeline
- 21-05-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: net/smc: avoid data corruption caused by decline We found a data corruption issue during testing of SMC-R on Redis applications. The benchmark has a low probability of reporting a strange error as shown below. "Error: Protocol error, got "\xe2" as reply type byte" Finally, we found that the retrieved error data was as follows: 0xE2 0xD4 0xC3 0xD9 0x04 0x00 0x2C 0x20 0xA6 0x56 0x00 0x16 0x3E 0x0C 0xCB 0x04 0x02 0x01 0x00 0x00 0x20 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0xE2 It is quite obvious that this is a SMC DECLINE message, which means that the applications received SMC protocol message. We found that this was caused by the following situations: client server ¦ clc proposal -------------> ¦ clc accept <------------- ¦ clc confirm -------------> wait llc confirm send llc confirm ¦failed llc confirm ¦ x------ (after 2s)timeout wait llc confirm rsp wait decline (after 1s) timeout (after 2s) timeout ¦ decline --------------> ¦ decline <-------------- As a result, a decline message was sent in the implementation, and this message was read from TCP by the already-fallback connection. This patch double the client timeout as 2x of the server value, With this simple change, the Decline messages should never cross or collide (during Confirm link timeout). This issue requires an immediate solution, since the protocol updates involve a more long-term solution.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated8.2HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
EPSS trend
Probability
0.67%
Chance of exploitation in the next 30 days
Percentile
52%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.67% 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: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu104 products
- linux< 5.15.0-100.110
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.15.0-1056.61
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44, < 5ada292b5c504720a0acef8cae9acc62a694d19c | ≥ 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44, < 90072af9efe8c7bd7d086709014ddd44cebd5e7c | ≥ 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44, < 94a0ae698b4d5d5bb598e23228002a1491c50add | ≥ 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44, < 7234d2b5dffa5af77fd4e0deaebab509e130c6b1 | ≥ 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44, < e6d71b437abc2f249e3b6a1ae1a7228e09c6e563 | 5.8
- linux_kernel≥ 5.8, < 5.10.203 | ≥ 5.11, < 5.15.141 | ≥ 5.16, < 6.1.65 | ≥ 6.2, < 6.6.4 | 6.7:rc1 | 6.7:rc2
Debian1 product
- linux< 6.1.66-1 | < 6.6.8-1
3 vendors · 107 products
