+MASTG-BEST-0021 Ensure Proper Error and Exception Handling (Android)

MASTG-BEST-0021 Ensure Proper Error and Exception Handling (Android)

Platform: Android
Knowledge: MASTG-KNOW-0010

Secure exception and error handling in Android is about preventing the leakage of sensitive information, managing failures gracefully, and ensuring that errors do not compromise security. User-facing error messages should remain generic, while controlled logging is reserved for developers. The OWASP DevGuide reinforces these principles with a focus on not disclosing internal details to end users, not disclosing sensitive user data to developers, and ensuring secure failure modes that do not weaken authentication or authorization.

Avoid leaking sensitive information: Error messages shown to users should be generic and not reveal internal details. Logs should be sanitized to remove sensitive data and restricted to authorized personnel. The official Log Info Disclosure guidance warns against including sensitive data or stack traces in production logs and recommends sanitization and reduced verbosity.
Fail securely: Exceptions must not weaken security controls. Any failure in security checks should result in a deny outcome, blocking the action rather than allowing weaker assumptions or insecure fallbacks. Security mechanisms should default to denying access until explicitly granted, since fail-open paths are a common attack vector.
Validate strictly and abort on errors: Unexpected formats or values should be treated as errors. Do not continue in a partially verified state. For example, if a network call succeeds at the transport layer but fails validation at the application layer, processing must stop. If the validation fails, do not try to sanitize the data to make the validation succeed.

See these resources for more details:

1. Ħarsa ġenerali

Titlu	Standard

1.1 Referenzi

1.2 Rekwiżiti identifikati

1.3 Regolamenti relatati

2. Rekwiżiti identifikati

Rekwiżiti
Sors	Rekwiżit

3. Regolamenti relatati

Regolamenti
Sors	Regolamentazzjoni

Kwistjonijiet marbuta

Links
Tip ta’ link	Kwistjoni
is related to	MASTG-TEST-0282 Unsafe Custom Trust Evaluation (Android)
is related to	MASTG-TEST-0284 Incorrect SSL Error Handling in WebViews (Android)

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- OWASP Application Security Verification Standard (ASVS) 5.0.0, May 2025, from OWASP/ASVS: © 2008-2025 The OWASP Foundation, licensed under CC BY-SA 4.0. Changes: divided into sections and converted into the GRCA format, the wording unchanged. These adaptations are shared under CC BY-SA 4.0 as well.
- OWASP Mobile Application Security Verification Standard (MASVS) v2.1.0, January 2024, from OWASP/masvs: © The OWASP Foundation, licensed under CC BY-SA 4.0. Changes: converted into the GRCA format, the wording unchanged. These adaptations are shared under CC BY-SA 4.0 as well.
- OWASP Mobile Application Security Weakness Enumeration (MASWE) v1.0.0, August 2026, from OWASP/maswe: © The OWASP Foundation, licensed under CC BY-SA 4.0. Changes: converted into the GRCA format, the wording unchanged, linked to the MASVS controls they map to. These adaptations are shared under CC BY-SA 4.0 as well.
- OWASP Mobile Application Security Testing Guide (MASTG) v2.0.0, June 2026, from OWASP/mastg: © The OWASP Foundation, licensed under CC BY-SA 4.0. The tests and best practices only, without code samples, images, tools or apps. Changes: converted into the GRCA format, the wording unchanged; references to other pages of the MASTG as links to mas.owasp.org; the weakness of each test in the numbering of MASWE v1 and linked to it. These adaptations are shared under CC BY-SA 4.0 as well.
- OWASP Software Assurance Maturity Model (SAMM) v2.2.0, July 2026, from owaspsamm/core: © The OWASP Foundation, licensed under CC BY-SA 4.0. Changes: converted into the GRCA format, the wording unchanged; short codes (G-SM-1-A) built from the model, the assessment questions as assessment procedures of their activities. These adaptations are shared under CC BY-SA 4.0 as well.
- OWASP Top 10:2025, from OWASP/Top10: © 2003-2025 The OWASP® Foundation, Inc., licensed under CC BY-SA 4.0. The ten categories, without the icons. Changes: converted into the GRCA format, the wording unchanged. These adaptations are shared under CC BY-SA 4.0 as well. The names of the mapped CWEs (Common Weakness Enumeration): © 2006–2026 The MITRE Corporation. License: The MITRE Corporation hereby grants you a non-exclusive, royalty-free license to use CWE for research, development, and commercial purposes. Any copy you make for such purposes is authorized on the condition that you reproduce MITRE’s copyright designation and this license in any such copy. See the CWE Terms of Use. CWE™ is a trademark of The MITRE Corporation.
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- OWASP Application Security Verification Standard (ASVS) 5.0.0, Mai 2025, aus OWASP/ASVS: © 2008-2025 The OWASP Foundation, lizenziert unter CC BY-SA 4.0. Änderungen: in Abschnitte aufgeteilt und in das GRCA-Format umgewandelt, der Wortlaut unverändert. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0.
- OWASP Mobile Application Security Verification Standard (MASVS) v2.1.0, Januar 2024, aus OWASP/masvs: © The OWASP Foundation, lizenziert unter CC BY-SA 4.0. Änderungen: in das GRCA-Format umgewandelt, der Wortlaut unverändert. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0.
- OWASP Mobile Application Security Weakness Enumeration (MASWE) v1.0.0, August 2026, aus OWASP/maswe: © The OWASP Foundation, lizenziert unter CC BY-SA 4.0. Änderungen: in das GRCA-Format umgewandelt, der Wortlaut unverändert, mit den MASVS-Controls verknüpft, denen sie zugeordnet sind. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0.
- OWASP Mobile Application Security Testing Guide (MASTG) v2.0.0, Juni 2026, aus OWASP/mastg: © The OWASP Foundation, lizenziert unter CC BY-SA 4.0. Nur die Tests und Best Practices, ohne Codebeispiele, Bilder, Werkzeuge und Apps. Änderungen: in das GRCA-Format umgewandelt, der Wortlaut unverändert; Verweise auf andere Seiten des MASTG als Links zu mas.owasp.org; die Schwachstelle jedes Tests in der Nummerierung der MASWE v1 und mit ihr verknüpft. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0.
- OWASP Software Assurance Maturity Model (SAMM) v2.2.0, Juli 2026, aus owaspsamm/core: © The OWASP Foundation, lizenziert unter CC BY-SA 4.0. Änderungen: in das GRCA-Format umgewandelt, der Wortlaut unverändert; Kürzel (G-SM-1-A) aus dem Modell gebildet, die Assessment-Fragen als Prüfverfahren ihrer Aktivitäten. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0.
- OWASP Top 10:2025, aus OWASP/Top10: © 2003-2025 The OWASP® Foundation, Inc., lizenziert unter CC BY-SA 4.0. Die zehn Kategorien, ohne die Symbole. Änderungen: in das GRCA-Format umgewandelt, der Wortlaut unverändert. Diese Bearbeitungen stehen ebenfalls unter CC BY-SA 4.0. Die Namen der zugeordneten CWEs (Common Weakness Enumeration): © 2006–2026 The MITRE Corporation. MITRE erlaubt die Nutzung für Forschung, Entwicklung und kommerzielle Zwecke, wenn jede Kopie den Urheberrechtsvermerk und die Lizenz enthält; maßgeblich ist der englische Wortlaut der Lizenz oben und die CWE Terms of Use. CWE™ ist eine Marke der MITRE Corporation.