Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcaca85b6f689293…

MALICIOUS

PDF

72.9 KB Created: 2021-04-04 03:56:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 98100c2a56ae0dbb32ea367c42c09468 SHA-1: 08f23945985a51f8fcef5a485c31395e20cdecb1 SHA-256: bcaca85b6f689293d530960a1aedd6206ea9be7ee2a069a550e3074cf3098c85
126 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness, with the PDF containing numerous external links, many hosted on disposable domains, suggesting a link farm for phishing or malware distribution. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and a date, indicating it was likely generated programmatically to appear as a search result or informational page, directing users to potentially harmful external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://cdn-cms.f-static.net/uploads/4475000/normal_60324ac4053bc.pdf In PDF document text
    • https://static.s123-cdn-static.com/uploads/4448538/normal_5ff88be02ddfd.pdfIn PDF document text
    • https://cdn.sqhk.co/puwipaneke/bMGBciK/frontline_commando_d_day_hack_mod_apk_download.pdfIn PDF document text
    • https://nizevamil.weebly.com/uploads/1/3/2/8/132814567/f87dce3a66031b8.pdfIn PDF document text
    • http://kesuvajeb.scienceontheweb.net/midox.pdfIn PDF document text
    • https://cdn.sqhk.co/letarezetap/6hdigjb/calligraphy_fonts_free_marathi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367007/normal_6057a399016df.pdfIn PDF document text
    • https://gasulemuj.weebly.com/uploads/1/3/4/3/134352818/7439212.pdfIn PDF document text
    • http://dizurexemubegog.mygamesonline.org/46713420962.pdfIn PDF document text
    • https://patobusogeziwe.weebly.com/uploads/1/3/4/0/134096506/3279784.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4365542/normal_5fcbaee67cb40.pdfIn PDF document text
    • https://cdn.sqhk.co/kimazibo/eayzH2d/spiky_ball_iphone_games.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369632/normal_6015e479c85ab.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/wb/ENAH/~3/dN4lCoxrs6M/wb?keyword=how%20to%20get%20hp%20deskjet%202700%20onlinePDF link annotation
    • https://uploads.strikinglycdn.com/files/f35f3fe6-17b5-495f-9238-bd1461e5c730/what_to_do_when_your_keurig_says_descale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/75478a94-aabe-4e84-821d-3912463ce874/zaguzulokufatiwax.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5ed39ac-f317-47fb-94b7-db9b70701ea4/homelite_330_chainsaw_for_sale.pdfIn PDF document text
    • http://bodirinukamole.onlinewebshop.net/does_a_verizon_phone_work_with_straight_talk.pdfIn PDF document text
    • http://nixomirorubu.myartsonline.com/9212326027.pdfIn PDF document text
    • https://s3.amazonaws.com/tibitexil/abbai_class_ammai_mass_telugu_movie.pdfIn PDF document text
    • https://s3.amazonaws.com/sobaketemu/programming_in_objective_c_free_download.pdfIn PDF document text
    • http://rolubumemetujin.atwebpages.com/broken_silence_natasha_preston_download.pdfIn PDF document text
    • https://s3.amazonaws.com/sevoga/cdc_vaccine_information_sheet_for_hepatitis_b.pdfIn PDF document text
    • https://s3.amazonaws.com/podawakumepewez/c_form-_factor_pluggable_cfp.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_off0000dfb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB1 5464 bytes
SHA-256: 65a99989c967ee6e66195b8a17473fe086536c61153ee6dc64363b4a16e88150
font_01_sfnt_off0000f26d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26D 10672 bytes
SHA-256: a5b7d30ceeee59b1e83683b20f6077e4fbcca8ba6906c93bd7d5217efcce3821