Client crash via unchecked ctime return
Published Mar 30, 2021 · Updated Aug 3, 2024
Denial of service in ircII before 20210314 allows remote attackers to crash the client and disconnect it via a crafted CTCP UTC message. The do_utc handler passes the parsed timestamp to ctime() and copies its return value without first checking for NULL; an invalid value makes ctime() fail. The attacker must share an IRC network with the victim and send the malformed UTC request; successful exploitation terminates only the victim's IRC client.
Summary
What happened
Denial of service in ircII before 20210314 allows remote attackers to crash the client and disconnect it via a crafted CTCP UTC message. The do_utc handler passes the parsed timestamp to ctime() and copies its return value without first checking for NULL; an invalid value makes ctime() fail. The attacker must share an IRC network with the victim and send the malformed UTC request; successful exploitation terminates only the victim's IRC client.
The record
- CVE
- CVE-2021-29376
- Published
- Mar 30, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 30, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
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Public exploit references
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Technologies
Your stack
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