Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bb8f479a4d0fea9…

MALICIOUS

PDF

96.0 KB Created: 2021-05-21 17:22:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1e9bed241439ec982897a801cef6cd7b SHA-1: e962a38ccfdc3f070111fa21d61e045b7dc9dac5 SHA-256: 6bb8f479a4d0fea977b09bafc9c442395ee297a0113533552f9799258318e529
156 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many of which point to other PDFs, suggesting a link farm or SEO manipulation tactic. One prominent URL, 'https://zajinet.ru/strik?utm_term=microeconomics+by+david+besanko+and+ronald+braeutigam+5th+edition+pdf', is embedded and likely serves as a lure to a malicious site. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://zajinet.ru/strik?utm_term=microeconomics+by+david+besanko+and+ronald+braeutigam+5th+edition+pdf
    • https://static.s123-cdn-static.com/uploads/4475737/normal_5fefc0c4c27e1.pdf
    • https://cdn-cms.f-static.net/uploads/4470220/normal_603fcf5cc7d19.pdf
    • https://niforobufuxir.weebly.com/uploads/1/3/4/5/134512868/bizoviramamuti-rukunimiw-wafozesuxifezur.pdf
    • https://jowiginuzag.weebly.com/uploads/1/3/1/4/131438641/dorawixudukosit.pdf
    • https://fexifeter.weebly.com/uploads/1/3/4/6/134612515/3209521.pdf
    • https://lovebaxubifutu.weebly.com/uploads/1/3/4/3/134322000/3500162.pdf
    • https://cdn-cms.f-static.net/uploads/4373526/normal_601e04c0cdd22.pdf
    • https://cdn-cms.f-static.net/uploads/4465147/normal_6047f044665de.pdf
    • https://cdn-cms.f-static.net/uploads/4413362/normal_602eb630000d9.pdf
    • https://dapoxegimore.weebly.com/uploads/1/3/0/9/130969679/juxirufopufe_lutud.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/ce4d539b-bcb3-424b-a7bb-68c4ce551b3c/strongs_bible_concordance_app.pdf
    • https://uploads.strikinglycdn.com/files/8e4b1683-d8dd-47bb-bf6a-82a389d70e5d/vazetol.pdf
    • https://uploads.strikinglycdn.com/files/cff1f055-794c-4c4a-8722-3668c82b1f9a/vebuzejop.pdf
    • https://s3.amazonaws.com/xilasisefi/royal_canin_pug_feeding_guide.pdf
    • https://uploads.strikinglycdn.com/files/227784f6-2a7f-449f-8766-376d35e51080/what_does_it_mean_when_my_vape_pen_is_blinking.pdf
    • https://uploads.strikinglycdn.com/files/d887ee04-8166-43d6-a8f7-e404a2f6a1c0/lg_g_pad_7.0_lte.pdf
    • https://uploads.strikinglycdn.com/files/da72c5e5-bc37-46a6-ab91-2661f6540a27/poker_super_system_2.pdf
    • https://uploads.strikinglycdn.com/files/48e35bf4-be6c-42d6-817f-6aa02c562f0e/kofixekofamujiweburifab.pdf
    • https://uploads.strikinglycdn.com/files/03360ad8-ccf5-44e7-b345-99df69d91a8a/gixuz.pdf
    • https://s3.amazonaws.com/xewamejixolefaj/ffiec_call_report_instructions_rc-_m.pdf
    • https://uploads.strikinglycdn.com/files/f9600c6e-9fb3-4291-8273-0c8c4a76cc93/vilppu_drawing_manual_review.pdf
    • https://uploads.strikinglycdn.com/files/2f56bf5d-06d0-4ae7-9e2d-666d4d82cf12/stopping_by_woods_on_a_snowy_evening_summary_slideshare.pdf
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012a0f.bin
962f181fd7b5982709d876f707af5a17c8fd447230d0c8698fe59ef05831e7b1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A0F 5944 bytes
font_01_sfnt_off00013e31.bin
1cc5e92865ad718f9db8a75d3dff3a2560393a46875b76babb69a11901ee4319
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E31 11000 bytes
font_02_sfnt_off000163b8.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x163B8 4324 bytes