CVE-2026-22903: wago 0852-1322_firmware Stack-based Buffer Overflow
CVSS: 9.8v3.1CriticalDeferred
Published 09-02-2026Last modified 09-02-2026
Vulnerability summary
CVE-2026-22903 is a critical (CVSS 9.8) Stack-based Buffer Overflow vulnerability in wago 0852-1322_firmware. EPSS estimates a 0.76% chance of exploitation in the next 30 days, higher than 54.7% of scored vulnerabilities.
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)EPSS score
0.76%
0%100%
Low · +0.08 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 09-02-2026PublishedVulnerability first disclosed.
- 09-02-2026Last modifiedVulnerability information updated.
Description
An unauthenticated remote attacker can send a crafted HTTP request containing an overly long SESSIONID cookie. This can trigger a stack buffer overflow in the modified lighttpd server, causing it to crash and potentially enabling remote code execution due to missing stack protections.
CVSS metrics
2 scores · 2 sources · 1 versionCritical 9.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 2 agree
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.76%
Chance of exploitation in the next 30 days
Percentile
55%
Versus all other CVEs
30-day change
+0.08 pp
From 0.68% on 21-09-2026
21-09-202621-10-2026
EPSS score0.76%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Wago2 products
- 0852-1322_firmware≥ 0.0.0, ≤ 2.64 | 2.64
- 0852-1328_firmware≥ 0.0.0, ≤ 2.64 | 2.64
1 vendor · 2 products