From 423a2bc737a908ad0c77bda470b2b59dc879936b Mon Sep 17 00:00:00 2001 From: Richard Levitte Date: Fri, 12 May 2023 10:00:13 +0200 Subject: Restrict the size of OBJECT IDENTIFIERs that OBJ_obj2txt will translate OBJ_obj2txt() would translate any size OBJECT IDENTIFIER to canonical numeric text form. For gigantic sub-identifiers, this would take a very long time, the time complexity being O(n^2) where n is the size of that sub-identifier. To mitigate this, a restriction on the size that OBJ_obj2txt() will translate to canonical numeric text form is added, based on RFC 2578 (STD 58), which says this: > 3.5. OBJECT IDENTIFIER values > > An OBJECT IDENTIFIER value is an ordered list of non-negative numbers. > For the SMIv2, each number in the list is referred to as a sub-identifier, > there are at most 128 sub-identifiers in a value, and each sub-identifier > has a maximum value of 2^32-1 (4294967295 decimal). Fixes otc/security#96 Fixes CVE-2023-2650 Reviewed-by: Matt Caswell Reviewed-by: Tomas Mraz --- CHANGES.md | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'CHANGES.md') diff --git a/CHANGES.md b/CHANGES.md index 5f301e189a..9378ed9c85 100644 --- a/CHANGES.md +++ b/CHANGES.md @@ -30,6 +30,32 @@ breaking changes, and mappings for the large list of deprecated functions. ### Changes between 3.0.8 and 3.0.9 [xx XXX xxxx] + * Mitigate for the time it takes for `OBJ_obj2txt` to translate gigantic + OBJECT IDENTIFIER sub-identifiers to canonical numeric text form. + + OBJ_obj2txt() would translate any size OBJECT IDENTIFIER to canonical + numeric text form. For gigantic sub-identifiers, this would take a very + long time, the time complexity being O(n^2) where n is the size of that + sub-identifier. ([CVE-2023-2650]) + + To mitigitate this, `OBJ_obj2txt()` will only translate an OBJECT + IDENTIFIER to canonical numeric text form if the size of that OBJECT + IDENTIFIER is 586 bytes or less, and fail otherwise. + + The basis for this restriction is RFC 2578 (STD 58), section 3.5. OBJECT + IDENTIFIER values, which stipulates that OBJECT IDENTIFIERS may have at + most 128 sub-identifiers, and that the maximum value that each sub- + identifier may have is 2^32-1 (4294967295 decimal). + + For each byte of every sub-identifier, only the 7 lower bits are part of + the value, so the maximum amount of bytes that an OBJECT IDENTIFIER with + these restrictions may occupy is 32 * 128 / 7, which is approximately 586 + bytes. + + Ref: https://datatracker.ietf.org/doc/html/rfc2578#section-3.5 + + *Richard Levitte* + * Fixed buffer overread in AES-XTS decryption on ARM 64 bit platforms which happens if the buffer size is 4 mod 5 in 16 byte AES blocks. This can trigger a crash of an application using AES-XTS decryption if the memory @@ -19626,6 +19652,7 @@ ndif +[CVE-2023-2650]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-2650 [CVE-2023-1255]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-1255 [CVE-2023-0466]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0466 [CVE-2023-0465]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0465 -- cgit v1.2.3