Home/CVE/urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserti
CVE

CVE-2020-26137

urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserti

urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.

MEDIUM · CVSS 6.5 EPSS 0.00279
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0

Affected Packages

1
Language-ecosystem packages (from OSV) tied to this CVE, with the version that fixes it - the dependency-level detail NVD doesn’t carry.
PyPI urllib3 MODERATE fixed in 1.25.9

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD30 Sep 2020 · 06:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Vendor Advisories

20
suse-csafopenSUSE-SU-2024:13212-1
suse-csafopenSUSE-SU-2024:13213-1
suse-csafSUSE-SU-2021:3251-1
suse-csafopenSUSE-SU-2021:1206-1
suse-csafopenSUSE-SU-2021:2817-1
🔗

References & Sources

8
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugs.python.org/issue39603Issue TrackingVendor Advisory
https://usn.ubuntu.com/4570-1/Third Party Advisory
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