7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.004 Low
EPSS
Percentile
69.4%
Due to incorrect buffer management ext_lm_group_acl is vulnerable to a denial of service attack when processing NTLM Authentication credentials. This problem is limited to installations using the
ext_lm_group_acl binary.
Squid 2.x -> 2.7.STABLE9
Squid 3.x -> 3.5.28
Squid 4.x -> 4.9
Due to incorrect input validation the NTLM authentication credentials parser in ext_lm_group_acl may write to memory outside the credentials buffer. On systems with memory access protections this can result in the helper process being terminated unexpectedly. Resulting in the Squid process also terminating and a denial of service for all clients using the proxy.
Advisory : http://www.squid-cache.org/Advisories/SQUID-2020_3.txt
An official patch is available from the Squid archives for both Squid 3.5 and Squid 4.
2019-11-11 : I reported the issue
2019-11-18 : I made a PR on GitHub with a fix
2019-11-22 : Fix was merged
See ‘Severity’ section of report.
7.5 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.004 Low
EPSS
Percentile
69.4%