Malicious PDF — malware analysis report

Static analysis result for SHA-256 99b1a93c6f3d526b…

MALICIOUS

PDF

86.7 KB Created: 2021-06-28 02:41:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 3ca4137dc3582de1a07cdb59d3af2fc5 SHA-1: 8a405faf565f42ecf1dfb2c78b5ebabc3547ae41 SHA-256: 99b1a93c6f3d526beabf25c218b33b19b6724575efe356465901260d1a6b5b40
164 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. The presence of a 'download' button heuristic further supports this, although the document body itself is heavily obfuscated and unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa8522363fc---48514201954.pdf In PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7592108430---40012227138.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbfe28a7035---45682159319.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/fm46esrsh7sanuncstn65tdnmh/manolemokiri.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/8b20f27613308977dff8142740e64679/57693866960.pdfIn PDF document text
    • http://chikatere.com/Upload/files/32241123833.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/0oqmds7bs3eg743cur2q0m9hs5/60425927844.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ee77ab322---sowuzasad.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/6hqem7qfg00enq5s8a8obl3lve/18259029876.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/5ckub5l9e7999nkgf11s4ofhpb/60101886876.pdfIn PDF document text
    • http://juentai.com/userfiles/files/jovodu.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/nuridabezavilokikenupeze.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9ca3d508a---74734832245.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/bisarefujigi.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/a9ff9af81b2f89288a753208b530b39d/52612477753.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160819525b6f48---69678819722.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/dti2dqa4gcb1a7lrj8gkhtdkap/10313456269.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/c2e3e3701229ee10589e18963492341b/fadenabevetimigokisivibin.pdfIn PDF document text
    • https://jgmurphy.com/wp-content/plugins/super-forms/uploads/php/files/500e768a2e2cfeade8e891d196107922/surolaxopimemefikul.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d6a1b482b---roparekajos.pdfIn PDF document text
    • https://arerp.kr/data/file///vakesaxetapexozafevurijiw.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/7b83f5dcaaa2138d26466990a3805a9d/tewagujovamezumod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=harrison%27s+hematology+and+oncology+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE1F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010631.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10631 17260 bytes
SHA-256: 3d147823ab4b761b7ef00b2b5ae44cce40fc003793cdbe6a5d88bb5d78fa792c
font_02_sfnt_off000133a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133A7 11204 bytes
SHA-256: 399ed0a2039a6b1fb6383dc3f0ac6d766bb75e5d127da1484a9d4a6de189e28a