Vulnerabilities > CVE-2020-27853 - Use of Externally-Controlled Format String vulnerability in Wire products
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
HIGH Integrity impact
HIGH Availability impact
HIGH Summary
Wire before 2020-10-16 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via a format string. This affects Wire AVS (Audio, Video, and Signaling) 5.3 through 6.x before 6.4, the Wire Secure Messenger application before 3.49.918 for Android, and the Wire Secure Messenger application before 3.61 for iOS. This occurs via the value parameter to sdp_media_set_lattr in peerflow/sdp.c.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Format String Injection An attacker includes formatting characters in a string input field on the target application. Most applications assume that users will provide static text and may respond unpredictably to the presence of formatting character. For example, in certain functions of the C programming languages such as printf, the formatting character %s will print the contents of a memory location expecting this location to identify a string and the formatting character %n prints the number of DWORD written in the memory. An attacker can use this to read or write to memory locations or files, or simply to manipulate the value of the resulting text in unexpected ways. Reading or writing memory may result in program crashes and writing memory could result in the execution of arbitrary code if the attacker can write to the program stack.
- String Format Overflow in syslog() This attack targets the format string vulnerabilities in the syslog() function. An attacker would typically inject malicious input in the format string parameter of the syslog function. This is a common problem, and many public vulnerabilities and associated exploits have been posted.
References
- http://github.security.telekom.com/2020/11/wire-secure-messenger-format-string-vulnerability.html
- http://github.security.telekom.com/2020/11/wire-secure-messenger-format-string-vulnerability.html
- https://github.com/wireapp/wire-audio-video-signaling/issues/23#issuecomment-710075689
- https://github.com/wireapp/wire-audio-video-signaling/issues/23#issuecomment-710075689