Malicious PDF — malware analysis report

Static analysis result for SHA-256 a527f2aaae98a6e1…

MALICIOUS

PDF

72.6 KB Created: 2021-03-28 00:21:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 432d3ec2e7d6ccbd0424b24cac8bd38a SHA-1: 7c46f276cabf39cdce09f8de216e773d0165d5c1 SHA-256: a527f2aaae98a6e142b1d1432733f8d4234e9a3491588be537492f43af5602e9
184 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link pointing to 'dafemum.ru'. The ML classifier also strongly indicated maliciousness. While no scripts were extracted, the embedded URL is the primary indicator of malicious intent, likely leading to a phishing or malware download site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://dafemum.ru/strik?utm_term=health+and+safety+engineer+job+openings In PDF document text
    • https://cdn-cms.f-static.net/uploads/4479916/normal_604fc9d82f0a4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415304/normal_6027f3a9216ba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445341/normal_60463e409a5af.pdfIn PDF document text
    • https://cdn.sqhk.co/texirova/ingeP4M/miburokivevizoziza.pdfIn PDF document text
    • https://cdn.sqhk.co/gudijupimeb/giN1Tib/wiseli.pdfIn PDF document text
    • https://cdn.sqhk.co/tifomogoketu/ijheic8/youtube_music_app_review.pdfIn PDF document text
    • https://fuzefiwojagolo.weebly.com/uploads/1/3/5/3/135308179/pimogadabisobiki.pdfIn PDF document text
    • http://xamejaduxak.22web.org/14326501987.pdfIn PDF document text
    • https://silatasetexa.weebly.com/uploads/1/3/1/6/131637876/melejikig_diwunumaje_pebewuravuxelaf_salosedatu.pdfIn PDF document text
    • https://cdn.sqhk.co/bubiwalifeda/XjF6yhi/51905391393.pdfIn PDF document text
    • http://penodesige.iblogger.org/wevidonetafaxewibel.pdfIn PDF document text
    • https://cdn.sqhk.co/melipetoluf/hibROjb/85368602395.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/tokit/hungry_shark_evolution_android_oyun_club_hile.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/601f2b95-bad0-4c7a-9836-d44ddf3bd9b3/gopro_hero_3_charger_cable_type.pdfIn PDF document text
    • http://lomurobutu.epizy.com/22016160054.pdfIn PDF document text
    • https://s3.amazonaws.com/ropidadegaxut/cyberstart_assess_answers_2020.pdfIn PDF document text
    • http://vusolitadiro.rf.gd/chemistry_practical_book_class_12_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/28e744c9-3e94-444a-9ff6-8695fd03640d/diary_of_a_wimpy_kid_long_haul_movie_actors.pdfIn PDF document text
    • https://s3.amazonaws.com/savukojubusum/what_are_the_ethical_standards_on_educational_leadership.pdfIn PDF document text
    • https://s3.amazonaws.com/gonasidupij/qu_significa_languidece_segn_la_biblia.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB85 5584 bytes
SHA-256: 60b9ae735f99c62c0770bd951a372efb52d23a0f2f3f03a1acaa49434de5d438
font_01_sfnt_off0000ee85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE85 11416 bytes
SHA-256: e51d2d0d34a49cf9ac54f24a01654e09a2744970ac6a870f0e89eb94ec941abb