CVE-2021-47295

CVE-2021-47295 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: net: sched: fix memory leak in tcindex_partial_destroy_work Syzbot reported memory leak in tcindex_set_parms(). The problem was in non-freed perfect hash in tcindex_partial_destroy_work(). In tcindex_set_parms() new tcindex_data is allocated and some fields from old one are copied to new one, but not the perfect hash. Since tcindex_partial_destroy_work() is the destroy function for old tcindex_data, we need to free perfect hash to avoid memory leak.

Frequently asked questions

What is CVE-2021-47295?
In the Linux kernel, the following vulnerability has been resolved: net: sched: fix memory leak in tcindex_partial_destroy_work Syzbot reported memory leak in tcindex_set_parms(). The problem was in non-freed perfect hash in tcindex_partial_destroy_work(). In tcindex_set_parms() new tcindex_data is allocated and some fields from old one are copied to new one, but not the perfect hash. Since tcindex_partial_destroy_work() is the destroy function for old tcindex_data, we need to free perfect hash to avoid memory leak.
How severe is CVE-2021-47295?
CVE-2021-47295 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47295 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47295?
CVE-2021-47295 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-47295?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2021-47295 have an EU (EUVD) identifier?
Yes. CVE-2021-47295 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34300.
When was CVE-2021-47295 published?
CVE-2021-47295 was published on 2024-05-21 and last updated on 2026-06-17.

References

Affected products (3)

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