{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-74577 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-74577 is a vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-74577 and fix it if it is affected.\n\nWhat it is: CVE-2026-74577 is a vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-74577 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-74577/ (Markdown: https://insights.sbomify.com/CVE-2026-74577/index.md)","id":"CVE-2026-74577","markdown":"https://insights.sbomify.com/CVE-2026-74577/index.md","name":"CVE-2026-74577","record":{"aliases":["AZL-96354","BELL-CVE-2026-74577","DEBIAN-CVE-2026-74577","GHSA-c2h5-j92r-8w96","UBUNTU-CVE-2026-74577"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_read"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"An attacker with local access can trigger an uninitialized memory leak in the Linux kernel MPLS routing code, exposing heap data.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mpls: initialize rtm_tos in mpls_getroute()\n\nmpls_getroute() builds the RTM_NEWROUTE reply to an RTM_GETROUTE\nrequest by filling a struct rtmsg allocated from an skb whose data\narea is not zeroed (alloc_skb(NLMSG_GOODSIZE, ...)). It sets every\nfield of the header except rtm_tos:\n\n\tr = nlmsg_data(nlh);\n\tr-\u003ertm_family\t = AF_MPLS;\n\tr-\u003ertm_dst_len\t= 20;\n\tr-\u003ertm_src_len\t= 0;\n\tr-\u003ertm_table\t= RT_TABLE_MAIN;\n\tr-\u003ertm_type\t= RTN_UNICAST;\n\tr-\u003ertm_scope\t= RT_SCOPE_UNIVERSE;\n\tr-\u003ertm_protocol = rt-\u003ert_protocol;\n\tr-\u003ertm_flags\t= 0;\n\nstruct rtmsg has no padding, so the one uninitialised byte rtm_tos\n(offset 3) is copied straight to user space on recvmsg(), leaking a\nbyte of uninitialised heap memory. This is in contrast to\nmpls_dump_route(), which fills the very same header and does set\nrtm_tos = 0.\n\nInitialize rtm_tos to 0, matching mpls_dump_route().\n\nReproduced with KMSAN by adding an MPLS route and issuing a\nnon-RTM_F_FIB_MATCH RTM_GETROUTE for its label:\n\n  BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x36c/0x33f0\n   _copy_to_iter+0x36c/0x33f0\n   __skb_datagram_iter+0x196/0x12c0\n   skb_copy_datagram_iter+0x5b/0x210\n   netlink_recvmsg+0x37b/0xef0\n   ...\n  Uninit was created at:\n   __alloc_skb+0x8ca/0x10e0\n   mpls_getroute+0x1280/0x3a40\n   rtnetlink_rcv_msg+0x1138/0x15a0\n   ...\n  Byte 19 of 64 is uninitialized\n\n(byte 19 = nlmsghdr(16) + rtmsg offset 3 = rtm_tos)","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"net: mpls: initialize rtm_tos in mpls_getroute()","id":"CVE-2026-74577","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"information_disclosure","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"crypto: algif_skcipher - force synchronous processing on trees without ctx-\u003estate","id":"CVE-2026-74578"},"packages":[],"prev":{"headline":"mm/slab: prevent unbounded recursion in free path with new kmalloc type","id":"CVE-2026-74576"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-19","vendors":["Linux"]},"summary":"An attacker with local access can trigger an uninitialized memory leak in the Linux kernel MPLS routing code, exposing heap data.","url":"https://insights.sbomify.com/CVE-2026-74577/"}