Malicious PDF — malware analysis report

Static analysis result for SHA-256 331b71cbaa64d599…

MALICIOUS

PDF

80.4 KB Created: 2021-03-28 11:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: f39b3d80aa2b4441cb674d5159543800 SHA-1: 985a50f393fc5c3698ff12835546222d9a96c83a SHA-256: 331b71cbaa64d5997f49732aa5f38da23d7fae4289db2f7aaf0f64a7c6b2d23b
194 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://gimoguvi.ru/strik?utm_term=do+you+capitalize+the+first+word+in+a+block+quote PDF link annotation
    • https://jinunezig.weebly.com/uploads/1/3/4/3/134308797/8789966.pdfIn PDF document text
    • http://edalovert.xyz/fifijadakug1ox4.pdfIn PDF document text
    • https://cdn.sqhk.co/boxokozofe/wthhih0/19971576892.pdfIn PDF document text
    • http://podcard2020.site/68946405982dbz3b.pdfIn PDF document text
    • https://bivesazi.weebly.com/uploads/1/3/4/6/134652180/3014915.pdfIn PDF document text
    • https://vakilelem.weebly.com/uploads/1/3/1/3/131379598/1335692.pdfIn PDF document text
    • https://fixaporaxaju.weebly.com/uploads/1/3/1/4/131413905/02a4a7a1.pdfIn PDF document text
    • https://lekusilikeveb.weebly.com/uploads/1/3/0/7/130739001/pijalok-liborub-kuparilukuk.pdfIn PDF document text
    • http://presalon.xyz/octavia_butler_wild_seed_quotesuhpgy.pdfIn PDF document text
    • https://cdn.sqhk.co/lepemafe/c4jbidH/zufodopol.pdfIn PDF document text
    • http://load-bcp.com/frigidaire_12000_btu_air_conditioner_portabledavlg.pdfIn PDF document text
    • https://cdn.sqhk.co/lafuwexale/ijTHhhO/77731544882.pdfIn PDF document text
    • https://cdn.sqhk.co/lisesemafo/TihNdjj/monster_truck_offroad_mad_truck_race_official.pdfIn PDF document text
    • http://klossheff.xyz/roruzojuvibigoxunazakozhsq8.pdfIn PDF document text
    • https://bugasidajuw.weebly.com/uploads/1/3/1/8/131856032/3d496d0bc11f3.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/7df86600-a11a-42fc-ab45-2cd43f33ab46/33787821281.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1f3b721-a9c1-4d36-a0f0-64f1e912e033/why_does_daphnia_heart_rate_increase_with_caffeine.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d0536fc-bb5a-4f12-8e8f-6d6741daed1e/duromax_generator_cover.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a47d9162-cce6-450b-a87a-093833f47752/wifi_extender_compatible_with_fios_g1100_router.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/48cb4711-77d2-4b61-9a3a-b6ddd145f4d5/69723693114.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b452d76-d07b-4e70-bb06-7975b7569812/how_to_use_ernesto_safety_can_opener.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b1e8b00-1a64-4e28-93c9-d7a4161d736d/20049693649.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/79f06418-c56f-4c17-8f17-98672e1dce1d/firestars_quest_full_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3360d47e-a963-4149-8762-40842e5ab0f2/77228602974.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_off0000fa8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8F 5816 bytes
SHA-256: b2be7ee82867118d5bc3052037179ca57b1e04aa2e7ed9679d45bcc4e56ab3ae
font_01_sfnt_off00010e7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E7B 10928 bytes
SHA-256: f824b4d5c7b74aa4dedfd8a578601d3c22335a963adf7e642f8d934823329d20