Malicious PDF — malware analysis report

Static analysis result for SHA-256 772bf3e6591e3c6e…

MALICIOUS

PDF

85.6 KB Created: 2021-06-14 06:15:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: fb7da9e4c39f2c0b7ce3167add458e1f SHA-1: d5a6631c4f27e4006eaff588a5e0e298bc8d2f7e SHA-256: 772bf3e6591e3c6e78ea325e26e86ceed9e21871c69553ad9af4c94372865a6d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document contains a link farm pointing to compromised WordPress sites, likely serving as a lure to download a malicious application, as suggested by the 'fallout shelter online apk' UTM parameter. The presence of multiple links on disposable hosting and compromised CMS uploads further supports a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://archism.ru/uplcv?utm_term=fallout+shelter+online+apk PDF link annotation
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/l5669sdatvo5307rs2ueinp8p6/47278571920.pdfIn PDF document text
    • http://vejwun.cz/images/59107737650.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947c68470df---dotaperulipikumud.pdfIn PDF document text
    • http://deauville.ru/files/file/revosobaku.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4309d7a85---72387408925.pdfIn PDF document text
    • http://vankouwenenmastop.nl/UserFiles/file/verugudototironedujotub.pdfIn PDF document text
    • http://mdc.ir/ckfinder/userfiles/files/22196216762.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d2627cf1e---18851249247.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606e461337d08---69239363422.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/rapizi.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/664c3aaa6734c21eb68812be7f1c61aa/40590869577.pdfIn PDF document text
    • https://agermag.ro/mm/file/55517875700.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/zemowigumotasunide.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/wekekif.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e789.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE789 3092 bytes
SHA-256: 6a72040639fcd71050e80943e22e68bbff7cf4eeba596c9ca71b5b76e9bcab80
font_01_sfnt_off0000f283.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF283 4924 bytes
SHA-256: 9e80f81b8d669c0b3eefdf04dc0e25e1810227e7d5c7d69fb92a961274effdf8
font_02_sfnt_off0001033d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033D 22504 bytes
SHA-256: ffb1c2435add8cabd9c74a4c173975e10f2065e2a72f4d8b992cec4d12a1f4a9
font_03_sfnt_off00013399.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13399 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e