CVE-2026-42934: f5 dos Out-of-bounds Read
Vulnerability summary
CVE-2026-42934 is a medium (CVSS 6.3) Out-of-bounds Read vulnerability in f5 dos. EPSS estimates a 0.73% chance of exploitation in the next 30 days, higher than 53.4% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 3 · Related 5Timeline
- 13-05-2026PublishedVulnerability first disclosed.
- 08-06-2026Last modifiedVulnerability information updated.
Description
NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_charset_module module. When charset, source_charset, and charset_map and proxy_pass with disabled buffering ("off") directives are configured, unauthenticated attackers can send requests that with conditions beyond the attackers' control to cause a heap buffer over-read in the NGINX worker process, leading to limited disclosure of memory or a restart. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
CVSS metrics
10 scores · 7 sources · 2 versions- OSV · AlpineEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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
- OSV · UbuntuEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
- OSV · DebianEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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
- OSV · WolfiEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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
- NVDNIST6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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
- OSV · ChainguardEcosystem advisory · calculated6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/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
- OSV · UbuntuEcosystem advisory · calculated4.8MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
- NVDNIST4.8MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
EPSS trend
Probability
0.73%
Chance of exploitation in the next 30 days
Percentile
53%
Versus all other CVEs
30-day change
0.00 pp
From 0.73% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
F57 products
- dos≥ 4.3.0, ≤ 4.7.0 | 4.8.0
- nginx gateway fabric≥ 1.3.0, ≤ 1.6.2 | ≥ 2.0.0, ≤ 2.6.0
- nginx ingress controller≥ 3.5.0, ≤ 3.7.2 | ≥ 4.0.0, ≤ 4.0.1 | ≥ 5.0.0, ≤ 5.4.2
- nginx_instance_manager≥ 2.16.0, ≤ 2.22.0
- nginx open source≥ 0.3.50, < 1.30.1 | ≥ 0.3.50, ≤ 0.9.7 | ≥ 1.0.0, ≤ 1.30.0
Chainguard2 products
- nginx-mainline< 1.31.0-r0
- nginx-stable< 1.30.1-r0
Wolfi2 products
- nginx-mainline< 1.31.0-r0
- nginx-stable< 1.30.1-r0
Alpine1 product
- nginx< 1.26.3-r1 | < 1.28.3-r1 | < 1.30.1-r0
Debian1 product
- nginx< 1.22.1-9+deb12u7 | < 1.26.3-3+deb13u5 | < 1.30.0-4
Ubuntu1 product
- nginx< 1.4.6-1ubuntu3.9+esm6 | < 1.10.3-0ubuntu0.16.04.5+esm7 | < 1.14.0-0ubuntu1.11+esm2 | < 1.18.0-0ubuntu1.7+esm1 | < 1.18.0-6ubuntu14.12 | < 1.24.0-2ubuntu7.9 | < 1.28.0-6ubuntu1.4 | < 1.28.3-2ubuntu1.2
6 vendors · 14 products
