GLSA 200701-13: Fetchmail: Denial of Service and password disclosure

Title:Fetchmail: Denial of Service and password disclosure
Bugs: #160463


Fetchmail has been found to have numerous vulnerabilities allowing for Denial of Service and password disclosure.


Fetchmail is a remote mail retrieval and forwarding utility.

Affected packages

Package Vulnerable Unaffected Architecture(s)
net-mail/fetchmail < 6.3.6 >= 6.3.6 All supported architectures


Neil Hoggarth has discovered that when delivering messages to a message delivery agent by means of the "mda" option, Fetchmail passes a NULL pointer to the ferror() and fflush() functions when refusing a message. Isaac Wilcox has discovered numerous means of plain-text password disclosure due to errors in secure connection establishment.


An attacker could deliver a message via Fetchmail to a message delivery agent configured to refuse the message, and crash the Fetchmail process. SMTP and LMTP delivery modes are not affected by this vulnerability. An attacker could also perform a Man-in-the-Middle attack, and obtain plain-text authentication credentials of users connecting to a Fetchmail process.


There is no known workaround at this time.


All fetchmail users should upgrade to the latest version:

    # emerge --sync
    # emerge --ask --oneshot --verbose ">=net-mail/fetchmail-6.3.6"



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