Impact
ares_inet_net_pton() is vulnerable to a buffer underflow for certain ipv6 addresses, in particular "0::00:00:00/2" was found to cause an issue. C-ares only uses this function internally for configuration purposes which would require an administrator to configure such an address via ares_set_sortlist().
However, users may externally use ares_inet_net_pton() for other purposes and thus be vulnerable to more severe issues.
Patches
Fixed in 1.19.1
Workarounds
No workarounds are available.
Credit
Hannes Moesl
X41 D-SEC GmbH
Audit funded by Open Source Technology Improvement Fund (OSTIF)
Impact
ares_inet_net_pton() is vulnerable to a buffer underflow for certain ipv6 addresses, in particular "0::00:00:00/2" was found to cause an issue. C-ares only uses this function internally for configuration purposes which would require an administrator to configure such an address via ares_set_sortlist().
However, users may externally use ares_inet_net_pton() for other purposes and thus be vulnerable to more severe issues.
Patches
Fixed in 1.19.1
Workarounds
No workarounds are available.
Credit
Hannes Moesl
X41 D-SEC GmbH
Audit funded by Open Source Technology Improvement Fund (OSTIF)