CVE-2021-27377Public exploitNetwork attack vector

Memory corruption via stale pointers after reallocation

Published Feb 18, 2021 · Updated Aug 3, 2024

Use-after-free in the yottadb Rust crate before 1.2.0 allows attackers to trigger undefined behavior during database traversal. The subscript_next and subscript_prev wrappers can retain a pointer after reallocating an undersized variable or subscript buffer, then pass that freed address to ydb_subscript_next_st or ydb_subscript_prev_st. An application must call an affected wrapper with insufficient initial storage; the resulting undefined behavior can corrupt memory or crash the process.

CVSS severity9.8
Critical
EPSS probability1.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in the yottadb Rust crate before 1.2.0 allows attackers to trigger undefined behavior during database traversal. The subscript_next and subscript_prev wrappers can retain a pointer after reallocating an undersized variable or subscript buffer, then pass that freed address to ydb_subscript_next_st or ydb_subscript_prev_st. An application must call an affected wrapper with insufficient initial storage; the resulting undefined behavior can corrupt memory or crash the process.

The record

CVE
CVE-2021-27377
Published
Feb 18, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-416
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8RustSecCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-416Use After Free

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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