CVE-2026-90698: memcached mcmc Tokenizer proto_text.c try_read_command_asciiauth out-of-bounds
Vulnerability summary
CVE-2026-90698 is a medium (CVSS 6.9) vulnerability in memcached. EPSS estimates a 0.86% chance of exploitation in the next 30 days, higher than 58.5% of scored vulnerabilities. 1 public exploit is recorded.
Not severe (CVSS 6.9, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 1Timeline
- 14-09-2026PublishedVulnerability first disclosed.
- 15-09-2026Last modifiedVulnerability information updated.
Description
A security flaw has been discovered in memcached 1.6.41/1.6.42/1.6.43. This vulnerability affects the function try_read_command_asciiauth of the file proto_text.c of the component mcmc Tokenizer. The manipulation results in out-of-bounds read. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. Upgrading to version 1.6.44 is able to resolve this issue. The patch is identified as af05c9302bba508b736c3da1d5670f63fe8b7db4. You should upgrade the affected component.
CVSS metrics
10 scores · 4 sources · 4 versions- OSV · UbuntuEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
- OSV · DebianEcosystem advisory · calculated6.9MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- NVDNIST5.5MediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XDiffers
- OSV · UbuntuEcosystem advisory · calculated5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- NVDNIST5.0MediumAV:N/AC:L/Au:N/C:N/I:N/A:P
EPSS trend
Probability
0.86%
Chance of exploitation in the next 30 days
Percentile
59%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.86% 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
1 foundExploit Reference (protectiv.ph)
Maturity: unknown
Weaknesses
CWE · root cause- CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferThe product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.
- CWE-125Out-of-bounds ReadThe product reads data past the end, or before the beginning, of the intended buffer.
Affected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Debian1 product
- memcachedAll versions (No fix recorded) | < 1.6.45-1
Ubuntu1 product
- memcached< 1.6.14-1ubuntu0.3 | < 1.6.24-1ubuntu0.3 | < 1.6.40-1ubuntu0.3
2 vendors · 2 products
