Linux · Kernel
CVE-2026-53362
ipv6: account for fraggap on the paged allocation path
这是什么
In the Linux kernel, the following vulnerability has been resolved:
ipv6: account for fraggap on the paged allocation path
In __ip6_append_data(), when the paged-allocation branch is taken
(MSG_MORE / NETIF_F_SG / large fraglen), alloclen and pagedlen are
computed as
alloclen = fragheaderlen + transhdrlen;
pagedlen = datalen - transhdrlen;
datalen already includes fraggap (datalen = length + fraggap). When
fraggap is non-zero, this is not the first skb and transhdrlen is zero.
The fraggap bytes carried over from the previous skb are copied just past
the fragment headers in the new skb's linear area. The linear area is
therefore undersized by fraggap bytes while pagedlen is overstated by the
same amount, and the copy writes past skb->end into the trailing
skb_shared_info.
An unprivileged user can trigger this via a UDPv6 socket using
MSG_MORE together with MSG_SPLICE_PAGES.
The bad accounting was introduced by commit 773ba4fe9104 ("ipv6:
avoid partial copy for zc"). Before commit ce650a166335 ("udp6: Fix
__ip6_append_data()'s handling of MSG_SPLICE_PAGES"), the negative
copy value caused -EINVAL to be returned. That later commit allowed
MSG_SPLICE_PAGES to proceed in this case, making the corruption
triggerable.
The non-paged branch sets alloclen to fraglen, which already accounts
for fraggap because datalen does. Bring the paged branch in line by
adding fraggap to alloclen and subtracting it from pagedlen.
After this adjustment, copy no longer collapses to -fraggap on the
paged path, so remove the stale comment describing that old arithmetic.
Since a negative copy is no longer expected for a valid MSG_SPLICE_PAGES
case, remove the MSG_SPLICE_PAGES exception from the negative copy check.
CISA: Linux Kernel contains an unspecified vulnerability that can allow for privilege escalation via IPv6 networking subsystem. This vulnerability can impact multiple products, including but not limited to Suse, Red Hat, and other products using Linux.
该怎么做
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
美国联邦机构的修复期限：2026年8月30日
- 加入 CISA 列表
- 2026年8月27日
- 发布日期
- 2026年7月4日
- 严重程度
- 高 7.8 CVSS 3.1
- 未来 30 天遭受攻击的概率（EPSS）
- 0.7% 位列所有已知漏洞的前 46.7%
- 更多详情
- NVD · CVE.org · CISA
全部参考链接（6）
- https://git.kernel.org/stable/c/14200d435af9a9eeb444f529fc2f689a236b7962
- https://git.kernel.org/stable/c/65fb14cbebb0cd0eff903a22d33537ddc8b95769
- https://git.kernel.org/stable/c/46f201f8b4c39633a1fa3dc12459f506d470993d
- https://git.kernel.org/stable/c/6374fb9edf72c67a118a2c214a0dddd04c921e0a
- https://git.kernel.org/stable/c/e9eacf19281ea2498b36291b56c9606118c2d74e
- https://git.kernel.org/stable/c/736b380e28d0480c7bc3e022f1950f31fe53a7c5
Linux 的其他被利用漏洞
| 加入日期 | 漏洞 | 产品 | 严重程度 | 受攻击概率 |
|---|---|---|---|---|
| 2026年9月18日 | Improper Check for Unusual or Exceptional Conditions | Kernel | 严重 9.8 | 3.3% |
| 2026年9月18日 | Race Condition | Kernel | 高 7.8 | 1.6% |
| 2026年9月18日 | Out-of-Bounds Write | Kernel | 高 8.8 | 0.9% |
| 2026年8月26日 | Out-of-Bounds Write | Kernel | 高 7.8 | 8.9% |
| 2026年6月2日 | Improper Authentication | Kernel | 高 7.8 | 5.5% |
| 2026年5月1日 | Incorrect Resource Transfer Between Spheres | Kernel | 高 7.8 | 98% |
| 2026年1月26日 | Integer Overflow | Kernel | 高 7.8 | 15% |
| 2025年10月6日 | Heap Out-of-Bounds Write | Kernel | 高 8.3 | 79% |
来源：Known Exploited Vulnerabilities（CISA，公有领域）、CVE records（cve.org）和 EPSS（FIRST）。受攻击概率是 EPSS 对未来 30 天内有人尝试利用该漏洞的估计。