Search/CVE-2026-15603
● CVE — Medium

CVE-2026-15603

Vendormorgan projectProductmorganDiscoveredAug 28, 2026UpdatedAug 31, 2026

morgan is an HTTP request logger middleware for Node.js. In versions prior to 1.12.0, the internal helper that escapes log token values did not neutralize the Unicode line separator characters U+0085 (Next Line), U+2028 (Line Separator), and U+2029 (Paragraph Separator). An unauthenticated remote client can place these characters in an attacker-controlled log token, for example a Basic auth username surfaced through the remote-user token, so that Unicode-aware downstream log processing splits a single request log into multiple logical records. This is a log forging issue (CWE-117) and an incomplete-fix follow-up to CVE-2026-5078, which only addressed ASCII control characters. The issue is fixed in morgan 1.12.0, which extends the escaping set to cover these Unicode line separators.…

CVSS v3.1
5.3 MEDIUM
EPSS
0.40%
probability of exploitation in 30 days
CISA KEV
Not listed
no confirmed exploitation reported
News coverage
0
sources referencing this CVE
Related IOCs
0
seen in the same coverage
EPSS Trend
Aug 30, 2026 → Oct 26, 2026
▲ 0.16pp
0.24% → 0.40% over 3 tracked changes
CVSS v3.1 Detail
Attack VectorNETWORK
Attack ComplexityLOW
Privileges RequiredNONE
User InteractionNONE
ScopeUNCHANGED
ConfidentialityNONE
IntegrityLOW
AvailabilityNONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Connections
2 relationships
Timeline
disclosure → media coverage
Aug 28, 2026
Disclosure — published as a CVE record. · last revised by NVD Aug 31, 2026