Linux Kernel up to 5.19.8 HMAC Data net/ipv6/seg6.c out-of-bounds

Summaryinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 5.19.8. This issue affects some unknown processing of the file net/ipv6/seg6.c of the component HMAC Data Handler. The manipulation leads to out-of-bounds. This vulnerability is listed as CVE-2022-48687. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.19.8 and classified as problematic. This issue affects some unknown processing of the file net/ipv6/seg6.c of the component HMAC Data Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: fix out-of-bounds read when setting HMAC data. The SRv6 layer allows defining HMAC data that can later be used to sign IPv6 Segment Routing Headers. This configuration is realised via netlink through four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual length of the SECRET attribute, it is possible to provide invalid combinations (e.g., secret = "", secretlen = 64). This case is not checked in the code and with an appropriately crafted netlink message, an out-of-bounds read of up to 64 bytes (max secret length) can occur past the skb end pointer and into skb_shared_info: Breakpoint 1, seg6_genl_sethmac (skb=, info=) at net/ipv6/seg6.c:208 208 memcpy(hinfo->secret, secret, slen); (gdb) bt #0 seg6_genl_sethmac (skb=, info=) at net/ipv6/seg6.c:208 #1 0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600, extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 , family=, family=) at net/netlink/genetlink.c:731 #2 0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00, family=0xffffffff82fef6c0 ) at net/netlink/genetlink.c:775 #3 genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792 #4 0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 ) at net/netlink/af_netlink.c:2501 #5 0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803 #6 0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000) at net/netlink/af_netlink.c:1319 #7 netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=) at net/netlink/af_netlink.c:1345 #8 0xffffffff81dff9a4 in netlink_sendmsg (sock=, msg=0xffffc90000ba7e48, len=) at net/netlink/af_netlink.c:1921 ... (gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end $1 = 0xffff88800b1b76c0 (gdb) p/x secret $2 = 0xffff88800b1b76c0 (gdb) p slen $3 = 64 '@' The OOB data can then be read back from userspace by dumping HMAC state. This commit fixes this by ensuring SECRETLEN cannot exceed the actual length of SECRET.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2022-48687. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 4.14.293, 4.19.258, 5.4.213, 5.10.143, 5.15.68, 5.19.9 or 6.0 eliminates this vulnerability. Applying the patch dc9dbd65c803/f684c16971ed/3df71e11a477/076f2479fc5a/55195563ec29/56ad3f475482/84a53580c5d2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2024-1025). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• EMC Avamar
• Broadcom Brocade SANnav
• Dell NetWorker
• Open Source Linux Kernel

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.292
• 4.19.257
• 5.4.212
• 5.10.142
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
• 5.15.63
• 5.15.64
• 5.15.65
• 5.15.66
• 5.15.67
• 5.19.0
• 5.19.1
• 5.19.2
• 5.19.3
• 5.19.4
• 5.19.5
• 5.19.6
• 5.19.7
• 5.19.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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