OpenSSL have published a security advisory. Here's how it affects BoringSSL:
| CVE | Summary | Severity in OpenSSL | Impact to BoringSSL |
|---|---|---|---|
| CVE-2023-2650 | Possible DoS translating ASN.1 object identifiers | Moderate | Independently fixed in 2016. Impact to BoringSSL before 2016 was much lower. See discussion below. |
This is a result of integer-to-decimal conversion being quadratic in the width of the integer. OpenSSL allowed arbitrarily large OIDs and OID components when converting OIDs to the dotted-decimal representation, making the overall operation quadratic and thus a DoS risk when run on attacker-supplied OIDs.
While this conversion is typically unnecessary (OIDs can be compared using the binary encoding), some systems use the dotted-decimal form either for logging or as an internal representation of the OID. Per the advisory, OpenSSL 3.x does this as part of X.509 signature verification.
BoringSSL independently fixed the quadratic-time behavior in 2016 by limiting the conversion to components less than 2⁶⁴. Additionally, BoringSSL does not convert to dotted-decimal as part of X.509 signature verification. It only converts when callers specifically request a textual representation of some structure.