report_vbuild in report.c in Fetchmail before 6.4.20 sometimes omits initialization of the vsnprintf va_list argument which might allow mail servers to cause a denial of service or possibly have unspecified other impact via long error messages. NOTE: it is unclear whether use of Fetchmail on any realistic platform results in an impact beyond an inconvenience to the client user.

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OESA-2021-1314 fetchmail security update

Fetchmail is a remote mail retrieval and forwarding utility intended for use over on-demand TCP/IP links, like SLIP or PPP connections. Fetchmail supports every remote-mail protocol currently in use on the Internet POP2, POP3, RPOP, APOP, KPOP, all IMAPs, ESMTP ETRN, IPv6, and IPSEC for retrieval...

PT-2021-3695

Name of the Vulnerable Software and Affected Versions Fetchmail versions prior to 6.4.20 Description The issue is related to the report vbuild function in report.c, which sometimes omits initialization of the vsnprintf va list argument. This might allow mail servers to cause a denial of service o...