GHSA-g2vj-v28f-r7cf · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: slip: reject VJ receive...
In the Linux kernel, the following vulnerability has been resolved: slip: reject VJ receive packets on instances with no rstate array slhc_init() accepts rslots == 0 as a valid configuration, with the documented meaning of 'no receive compression'. In that case the allocation loop in slhc_init() is skipped, so comp->rstate stays NULL and comp->rslot_limit stays 0 (from the kzalloc of struct slcompress). The receive helpers do not defend against that configuration. slhc_uncompress() dereferences comp->rstate[x] when the VJ header carries an explicit connection ID, and slhc_remember() later assigns cs = &comp->rstate[...] after only comparing the packet's slot number to comp->rslot_limit. Because rslot_limit is 0, slot 0 passes the range check, and the code dereferences a NULL rstate. The configuration is reachable in-tree through PPP. PPPIOCSMAXCID stores its argument in a signed int, and (val >> 16) uses arithmetic shift. Passing 0xffff0000 therefore sign-extends to -1, so val2 + 1 is 0 and ppp_generic.c ends up calling slhc_init(0, 1). Because /dev/ppp open is gated by ns_capable(CAP_NET_ADMIN), the whole path is reachable from an unprivileged user namespace. Once the malformed VJ state is installed, any inbound VJ-compressed or VJ-uncompressed frame that selects slot 0 crashes the kernel in softirq context: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] RIP: 0010:slhc_uncompress (drivers/net/slip/slhc.c:519) Call Trace: <TASK> ppp_receive_nonmp_frame (drivers/net/ppp/ppp_generic.c:2466) ppp_input (drivers/net/ppp/ppp_generic.c:2359) ppp_async_process (drivers/net/ppp/ppp_async.c:492) tasklet_action_common (kernel/softirq.c:926) handle_softirqs (kernel/softirq.c:623) run_ksoftirqd (kernel/softirq.c:1055) smpboot_thread_fn (kernel/smpboot.c:160) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) </TASK> Reject the receive side on such instances instead of touching rstate. slhc_uncompress() falls through to its existing 'bad' label, which bumps sls_i_error and enters the toss state. slhc_remember() mirrors that with an explicit sls_i_error increment followed by slhc_toss(); the sls_i_runt counter is not used here because a missing rstate is an internal configuration state, not a runt packet. The transmit path is unaffected: the only in-tree caller that picks rslots from userspace (ppp_generic.c) still supplies tslots >= 1, and slip.c always calls slhc_init(16, 16), so comp->tstate remains valid and slhc_compress() continues to work.
総合評価: CVE-2026-45842 は低リスク（22.6/100）。CVSS 深刻度は中。悪用される可能性が高い（EPSS 0.11%、2 パーセンタイル） 推奨対応: 悪用情報と EPSS の推移を監視し、必要に応じて優先度を見直してください。
リスクは変動します。再評価に基づき、本ページの表示内容を更新しています。
EPSS は日次で悪用されやすさの相対度合いを推定します。パーセンタイルは採点済み CVE の中での相対位置（高いほど相対的に深刻）を示します。
| # | 日付 | 旧 EPSS スコア | 新 EPSS スコア | Δ（新 − 旧） |
|---|---|---|---|---|
| 1 | 2026-06-27 | 0.16% | 0.11% | -0.05% |
| 2 | 2026-06-15 | 0.02% | 0.16% | +0.15% |
| 3 | 2026-05-27 | — | 0.02% | — |
EPSS の全履歴 （全 3 件）
この CVE の CVSS 指標。
| ベーススコア | バージョン | 深刻度 | ベクトル | 悪用しやすさ | 影響 | スコアの出典 |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
GHSA-g2vj-v28f-r7cf · 深刻度： medium — In the Linux kernel, the following vulnerability has been resolved: slip: reject VJ receive...
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-45842 not yet assigned priority: Debian including 2 source packages (linux, linux-6.1), 6 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 6. | https://security-tracker.debian.org/tracker/CVE-2026-45842 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-45842 |
suse
|
medium | — | https://www.suse.com/security/cve/CVE-2026-45842/ |
ubuntu
|
medium | CVE-2026-45842 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1422 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1024, ignored 173, needed 141, released 84. | https://ubuntu.com/security/CVE-2026-45842 |
| ベンダー | 製品 | バージョン | 生の CPE |
|---|---|---|---|
| linux | linux_kernel | >= 2.6.32.70, < 2.6.33 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.2.75, < 3.3 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.4.111, < 3.5 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.10.96, < 3.11 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.12.53, < 3.13 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.14.60, < 3.15 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 3.18.27, < 3.19 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 4.1.17, < 4.2 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 4.3.5, < 5.10.258 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.11, < 5.15.209 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 5.16, < 6.1.175 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.2, < 6.6.141 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.7, < 6.12.91 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.13, < 6.18.33 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| linux | linux_kernel | >= 6.19, < 7.0.10 | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |