Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 3.32% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2021
CVE-2021-28131High confidence
Impala logs contain secrets
Apache Software Foundation · Apache Impala
7.5HighCVSS 3.1
Within 7 days
Fix not verifiedHigh technical severity; prioritise exposed affected systems while verifying vendor guidance.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:High, unchanged from published severity.unchanged
Compensating controls
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Apache Software Foundation Apache Impala and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
High technical severity; prioritise exposed affected systems while verifying vendor guidance.
Fix not verified01
What, why and how
Impala sessions use a 16 byte secret to verify that the session is not being hijacked by another user. However, these secrets appear in the Impala logs, therefore Impala users with access to the logs can use another authenticated user's sessions with specially constructed requests. This means the attacker is able to execute statements for which they don't have the necessary privileges otherwise. Impala deployments with Apache Sentry or Apache Ranger authorization enabled may be vulnerable to privilege escalation if an authenticated attacker is able to hijack a session or query from another authenticated user with privileges not assigned to the attacker. Impala deployments with audit logging enabled may be vulnerable to incorrect audit logging as a user could undertake actions that were logged under the name of a different authenticated user. Constructing an attack requires a high degree of technical sophistication and access to the Impala system as an authenticated user. Mitigation: If an Impala deployment uses Apache Sentry, Apache Ranger or audit logging, then users should upgrade to a version of Impala with the fix for IMPALA-10600. The Impala 4.0 release includes this fix. This hides session secrets from the logs to eliminate the risk of any attack using this mechanism. In lieu of an upgrade, restricting access to logs that expose secrets will reduce the risk of an attack. Restricting access to the Impala deployment to trusted users will also reduce the risk of an attack. Log redaction techniques can be used to redact secrets from the logs.
What
Impala sessions use a 16 byte secret to verify that the session is not being hijacked by another user. However, these secrets appear in the Impala logs, therefore Impala users with access to the logs can use another authenticated user's sessions with specially constructed requests. This means the attacker is able to execute statements for which they don't have the necessary privileges otherwise. Impala deployments with Apache Sentry or Apache Ranger authorization enabled may be vulnerable to privilege escalation if an authenticated attacker is able to hijack a session or query from another authenticated user with privileges not assigned to the attacker. Impala deployments with audit logging enabled may be vulnerable to incorrect audit logging as a user could undertake actions that were logged under the name of a different authenticated user. Constructing an attack requires a high degree of technical sophistication and access to the Impala system as an authenticated user. Mitigation: If an Impala deployment uses Apache Sentry, Apache Ranger or audit logging, then users should upgrade to a version of Impala with the fix for IMPALA-10600. The Impala 4.0 release includes this fix. This hides session secrets from the logs to eliminate the risk of any attack using this mechanism. In lieu of an upgrade, restricting access to logs that expose secrets will reduce the risk of an attack. Restricting access to the Impala deployment to trusted users will also reduce the risk of an attack. Log redaction techniques can be used to redact secrets from the logs.
Why
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.
What
Impala sessions use a 16 byte secret to verify that the session is not being hijacked by another user. However, these secrets appear in the Impala logs, therefore Impala users with access to the logs can use another authenticated user's sessions with specially constructed requests. This means the attacker is able to execute statements for which they don't have the necessary privileges otherwise. Impala deployments with Apache Sentry or Apache Ranger authorization enabled may be vulnerable to privilege escalation if an authenticated attacker is able to hijack a session or query from another authenticated user with privileges not assigned to the attacker. Impala deployments with audit logging enabled may be vulnerable to incorrect audit logging as a user could undertake actions that were logged under the name of a different authenticated user. Constructing an attack requires a high degree of technical sophistication and access to the Impala system as an authenticated user. Mitigation: If an Impala deployment uses Apache Sentry, Apache Ranger or audit logging, then users should upgrade to a version of Impala with the fix for IMPALA-10600. The Impala 4.0 release includes this fix. This hides session secrets from the logs to eliminate the risk of any attack using this mechanism. In lieu of an upgrade, restricting access to logs that expose secrets will reduce the risk of an attack. Restricting access to the Impala deployment to trusted users will also reduce the risk of an attack. Log redaction techniques can be used to redact secrets from the logs.
Why
The product requires authentication, but the product has an alternate path or channel that does not require authentication.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Authentication Bypass Using an Alternate Path or Channel → gain additional privileges
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- None
- Attack complexity
- High: exploitation depends on specific conditions
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-288 ↗
CWE-288: Authentication Bypass Using an Alternate Path or Channel. The product requires authentication, but the product has an alternate path or channel that does not require authentication.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix not verified
- Affected
- Apache Impala: Apache Impala ≤ 3.4.0
- Fixed
- No fixed version is explicitly recorded in the structured CVE data.
- Action
- No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 22 Jul 2021 · Last source change 3 Aug 2024, 21:33 UTC · CWE-288 · Authentication Bypass Using an Alternate Path or Channel
CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2021-14830
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.