HTTP response splitting via HTTP_HOST CRLF injection
Published Oct 20, 2021 · Updated Aug 3, 2024
CRLF injection in ZTE MF971R affected firmware allows remote attackers to modify HTTP response headers via crafted HTTP requests. The HTTP_HOST handling accepts attacker-controlled CRLF characters and incorporates them into generated response headers, enabling response splitting. Exploitation requires a victim to open an attacker-supplied URL reaching the router interface; the documented effect is header integrity manipulation rather than arbitrary code execution.
Summary
What happened
CRLF injection in ZTE MF971R affected firmware allows remote attackers to modify HTTP response headers via crafted HTTP requests. The HTTP_HOST handling accepts attacker-controlled CRLF characters and incorporates them into generated response headers, enabling response splitting. Exploitation requires a victim to open an attacker-supplied URL reaching the router interface; the documented effect is header integrity manipulation rather than arbitrary code execution.
The record
- CVE
- CVE-2021-21743
- Published
- Oct 20, 2021
- Updated
- Aug 3, 2024
- Vendor
- ZTE Corporation
- Product
- MF971R
- Classifications
- CWE-74
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Oct 20, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=BD_ZTE_MF971RV1.0.0B05, BD_PLKPLMF971R1V1.0.0B06, BD_MF971R2V1.0.0B03, BD_ZTE_MF971RS2V1.0.0B03, BD_ZTE_MF971RSV1.0.0B05
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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