CVE-2026-40561

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.36% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 29.9% of scored records. A rank, not a probability.

NVD base score

5.3 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-10-26.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-05-03 00:57Z5 MO AGO

Last updated

2026-05-07 16:45Z5 MO AGO

Reserved

2026-04-14

Assigning CNA

CPANSec

Record state

PUBLISHED

Severity

Medium (CVSS 5.3)

CNA CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weaknesses

• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base

Data version

5.2

Document digest

52b767d5ca38ccb8022c74200c239c9dcf3b662ad11613707bed2bb35a86935e

• datatracker.ietf.orghttps://datatracker.ietf.org/doc/html/rfc7230#section-3.3.3
• github.comhttps://github.com/kazuho/Starlet/commit/a7d5dfd1862aafa43e5eaca0fdb6acf4cc15b2d0.patchpatch
• metacpan.orghttps://metacpan.org/release/KAZUHO/Starlet-0.32/changesrelease-notes
• www.openwall.comhttp://www.openwall.com/lists/oss-security/2026/05/03/1