{"cve":"CVE-2022-48687","nvd":{"published":"2024-05-03T15:15:07.723","modified":"2026-06-17T05:15:55.323","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: sr: fix out-of-bounds read when setting HMAC data.\n\nThe SRv6 layer allows defining HMAC data that can later be used to sign IPv6\nSegment Routing Headers. This configuration is realised via netlink through\nfour attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and\nSEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual\nlength of the SECRET attribute, it is possible to provide invalid combinations\n(e.g., secret = \"\", secretlen = 64). This case is not checked in the code and\nwith an appropriately crafted netlink message, an out-of-bounds read of up\nto 64 bytes (max secret length) can occur past the skb end pointer and into\nskb_shared_info:\n\nBreakpoint 1, seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208\n208\t\tmemcpy(hinfo->secret, secret, slen);\n(gdb) bt\n #0  seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208\n #1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,\n    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 <init_net>, family=<optimized out>,\n    family=<optimized out>) at net/netlink/genetlink.c:731\n #2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,\n    family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775\n #3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792\n #4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>)\n    at net/netlink/af_netlink.c:2501\n #5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803\n #6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)\n    at net/netlink/af_netlink.c:1319\n #7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=<optimized out>)\n    at net/netlink/af_netlink.c:1345\n #8  0xffffffff81dff9a4 in netlink_sendmsg (sock=<optimized out>, msg=0xffffc90000ba7e48, len=<optimized out>) at net/netlink/af_netlink.c:1921\n...\n(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end\n$1 = 0xffff88800b1b76c0\n(gdb) p/x secret\n$2 = 0xffff88800b1b76c0\n(gdb) p slen\n$3 = 64 '@'\n\nThe OOB data can then be read back from userspace by dumping HMAC state. This\ncommit fixes this by ensuring SECRETLEN cannot exceed the actual length of\nSECRET.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","score":5.5},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/076f2479fc5a15c4a970ca3b5e57d42ba09a31fa","https://git.kernel.org/stable/c/3df71e11a4773d775c3633c44319f7acdb89011c","https://git.kernel.org/stable/c/55195563ec29f80f984237b743de0e2b6ba4d093","https://git.kernel.org/stable/c/56ad3f475482bca55b0ae544031333018eb145b3","https://git.kernel.org/stable/c/84a53580c5d2138c7361c7c3eea5b31827e63b35"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:49:23.840078609+00:00"},"epss":{"cve":"CVE-2022-48687","score":0.00244,"percentile":0.15657,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}