CVE-2023-49062

Katran could disclose non-initialized kernel memory as part of an IP header. The issue was present for IPv4 encapsulation and ICMP (v4) Too Big packet generation. After a bpf_xdp_adjust_head call, Katran code didn’t initialize the Identification field for the IPv4 header, resulting in writing content of kernel memory in that field of IP header. The issue affected all Katran versions prior to commit 6a03106ac1eab39d0303662963589ecb2374c97f

Weakness

The product does not initialize or incorrectly initializes a resource, which might leave the resource in an unexpected state when it is accessed or used.

Affected Software

Potential Mitigations

• Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, in Java, if the programmer does not explicitly initialize a variable, then the code could produce a compile-time error (if the variable is local) or automatically initialize the variable to the default value for the variable’s type. In Perl, if explicit initialization is not performed, then a default value of undef is assigned, which is interpreted as 0, false, or an equivalent value depending on the context in which the variable is accessed.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/26.html
• https://cwe.mitre.org/data/definitions/29.html

References

• https://github.com/facebookincubator/katran/commit/6a03106ac1eab39d0303662963589ecb2374c97f
• https://www.facebook.com/security/advisories/cve-2023-49062