Malicious PDF — malware analysis report

Static analysis result for SHA-256 52b8b295f31e90a9…

MALICIOUS

PDF

74.7 KB Created: 2021-05-08 03:00:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd3c5a2ed7c7390def98554e7f7e686b SHA-1: 276b5db85c5b2bdda41590ba78b65e5d84ba94b5 SHA-256: 52b8b295f31e90a9aa512b01e0934843b4afb4a3575d9a20e16afcc0e3c45b2d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URI pointing to 'https://kuzutuzo.ru/strik', which is likely the primary distribution point for a malicious payload or phishing page. The document body, though heavily obfuscated, suggests a lure related to a 'Boundaries in marriage study guide'. No scripts were extracted, but the presence of external URLs and the malware detection strongly indicate a phishing or malware delivery attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://kuzutuzo.ru/strik?utm_term=boundaries+in+marriage+study+guide
    • http://copytoshka.ru/evenflo_victory_plus_jogging_stroller_reviews752rn.pdf
    • http://budivabod.iblogger.org/56278228463.pdf
    • http://toluvubub.mygamesonline.org/the_celebrated_jumping_frog.pdf
    • http://nelezoroga.22web.org/besolexew.pdf
    • http://lnstagramverificationbadge.com/marine_corps_awards_manual_2017y66ac.pdf
    • http://ruxenawuxovogu.getenjoyment.net/3502349602.pdf
    • http://ersoil.fun/fonedog_android_toolkit_crackedxa589.pdf
    • http://chebsvet.ru/how_to_describe_rain_in_writing8jyc7.pdf
    • http://vashobereg.com/8553940201293i06.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/a4999bc8-3d2e-4813-b426-f716f03f5c5f/what_is_the_value_of_the_smallest_bond_angle_in_xecl4.pdf
    • https://7fd4abad-31f8-4c52-ae8e-93d0cc7f2af2.filesusr.com/ugd/910e70_9e3ebf27fca2477bb7a206e5f08e5ac9.pdf?index=true
    • http://nejesezape.myartsonline.com/paleo_diet_for_athletes_meal_plan.pdf
    • https://8641c524-1fb5-4292-87ed-dd72f64d6c22.filesusr.com/ugd/9b7d8a_ff1fe6ed58f8455a8bd8e34088b5d912.pdf?index=true
    • https://uploads.strikinglycdn.com/files/b8f88e66-2018-4279-88cf-5921793f97c9/netgear_3700_extender_firmware.pdf
    • https://uploads.strikinglycdn.com/files/00c659a7-ea40-4c10-8c41-ca3083a2b1b3/zujer.pdf
    • https://ee60c613-3dd1-430d-b711-08e3dcbf0273.filesusr.com/ugd/19ce5d_be4ede9e30a44c948b7020abe4657d29.pdf?index=true
    • https://c78267de-509c-4cb0-9394-6b21b7876e04.filesusr.com/ugd/290ce3_faaed1f7618b4f8199a7520094ea2306.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e5ea.bin
d3b04c330238cc7c01eb0d88c188eefa032386988ed4bf11a77053195d375183
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5EA 5264 bytes
font_01_sfnt_off0000f7c2.bin
de83f23f2de80f9ed9cc249dbb3996f454683ab48ce5ec1cbb42193b67dd580c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C2 10480 bytes