01 Record
CVE-2026-43969
Cookie Request Header Injection via Unvalidated Encoder in cow_cookie:cookie/1
LowPUBLISHEDCNA: EEF
CNA base score2.1 CVSS v4.0CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
02 Description
Cookie Request Header Injection via Unvalidated Encoder in cow_cookie:cookie/1
03 Exploitation and scoring
- 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.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.14% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 3.9% of scored records. A rank, not a probability.
- NVD base score
- 2.1 (CVSS v4.0), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- 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.
04 Metadata
- Published
- 2026-05-11 18:06Z5 MO AGO
- Last updated
- 2026-10-09 06:57Z20 DAYS AGO
- Reserved
- 2026-05-04
- Assigning CNA
- EEF
- Record state
- PUBLISHED
- Severity
- Low (CVSS 2.1)
- CNA CVSS vector
- CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
- Weaknesses
- CWE-93Improper Neutralization of CRLF Sequences ('CRLF Injection')Base
- Data version
- 5.2
- Document digest
- 0507aa859419aaeb4930aa2bfdb557d3b3b715b03c5fff06832c98a5d4ed099b
05 Affected products
VendorProductVersionsPlatforms
nineninescowlib2.9.0 to < 2.21.0, f017f8a0ecbffd5033d9ab49bf180186f7a523a7 to < c17fd73945ef536cccecc492d286fb6b6d1c3307—
06 References
- github.comGitHub Advisoryhttps://github.com/erlef/cowlib/commit/177953dd51540da11090666c1f007214127a1144
- cna.erlef.orgEEF CNA record for CVE-2026-43969https://cna.erlef.org/cves/CVE-2026-43969.html
- osv.devOSV record EEF-CVE-2026-43969https://osv.dev/vulnerability/EEF-CVE-2026-43969
- github.comIntroducing commit f017f8a in ninenines/cowlibhttps://github.com/ninenines/cowlib/commit/f017f8a0ecbffd5033d9ab49bf180186f7a523a7
- github.comFix commit c17fd73 in ninenines/cowlibhttps://github.com/ninenines/cowlib/commit/c17fd73945ef536cccecc492d286fb6b6d1c3307