CVE-2020-5247

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

2.54% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 84.6% of scored records. A rank, not a probability.

NVD base score

7.5 (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:H/A:N

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

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

2020-02-28 16:55Z6 YR AGO

Last updated

2024-08-04 08:22Z2 YR AGO

Reserved

2020-01-02

Assigning CNA

GitHub_M

Record state

PUBLISHED

Severity

Medium (CVSS 6.5)

CNA CVSS vector

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

Weaknesses

• CWE-113Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')Variant
• CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')Class

Data version

5.1

Document digest

2d7187d13f1fa7b20244c1d20a6907758b6747c22274f2d77adf49dba29b62e9

• github.comhttps://github.com/puma/puma/security/advisories/GHSA-84j7-475p-hp8vx_refsource_CONFIRM
• owasp.orghttps://owasp.org/www-community/attacks/HTTP_Response_Splittingx_refsource_MISC
• www.ruby-lang.orghttps://www.ruby-lang.org/en/news/2019/10/01/http-response-splitting-in-webrick-cve-2019-16254x_refsource_MISC
• lists.fedoraproject.orgFEDORA-2020-a3f26a9387https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJ3LL5F5QADB6LM46GXZETREAKZMQNRD/vendor-advisoryx_refsource_FEDORA
• lists.fedoraproject.orgFEDORA-2020-fd87f90634https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BMJ3CGZ3DLBJ5WUUKMI5ZFXFJQMXJZIK/vendor-advisoryx_refsource_FEDORA
• lists.fedoraproject.orgFEDORA-2020-08092b4c97https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DIHVO3CQMU7BZC7FCTSRJ33YDNS3GFPK/vendor-advisoryx_refsource_FEDORA
• lists.debian.org[debian-lts-announce] 20220525 [SECURITY] [DLA 3023-1] puma security updatehttps://lists.debian.org/debian-lts-announce/2022/05/msg00034.htmlmailing-listx_refsource_MLIST