02 Records
FEED: ACQUIRING
01 RecordSTATE: PUBLISHED
02 Description
CNA: GitHub_Mcpp-httplib: HTTP header value percent-decoding in server-side `parse_header` enables CRLF injection
03 Exploitation and scoring
SRC: CISA, FIRST, NVD, RED HAT- Exploitation
- Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.
- SSVC decision
- ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
- 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
- 0.29% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Ranks above 21.9% of scored records. A rank, not a probability.
- NVD base score
- 9.9 (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:C/C:L/I:H/A:L
- NVD analysis status
- Modified. NVD last modified this record on 2026-07-22.
- 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.
SCHEMA: 5.2
- Published
- 2026-05-29 19:21Z3 MO AGO
- Last updated
- 2026-06-01 17:57Z3 MO AGO
- Reserved
- 2026-05-12
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- Critical (CVSS 9.9)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:L
- Weaknesses
- CWE-93Improper Neutralization of CRLF Sequences ('CRLF Injection')Base
- CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base
- Data version
- 5.2
- Document digest
- 51d8dbb9720ad357c5b7cb8201b0a73c4fe2c976b7f5f47eef539b919bad84d6
05 Affected products
PAIRS: 1VendorProductVersionsPlatforms