Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c843a5f60e65b20…

MALICIOUS

PDF

86.6 KB Created: 2021-09-03 12:43:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1425609a85dcafde6d81894792c4492c SHA-1: 18b1736ace13cbed8f6797522a549a67301c2fb1 SHA-256: 9c843a5f60e65b209ad7146bedcb77986de05b266ce9f868db81908c3f4d4258
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it is a link farm and a callback phishing lure. The document body is heavily obfuscated, but the presence of multiple external URIs and the 'SE_CALLBACK_LURE' heuristic strongly suggest a phishing attempt designed to trick the user into initiating a phone call. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://insk.ru/img/userfiles/file/lopudoba.pdf In PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160887a7f66351---tajepuzojegile.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/bawexulowopi.pdfIn PDF document text
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/fa1c2e52c3290bba71b05b5c48af3fca/4797550354.pdfIn PDF document text
    • https://proxus.nl/file/puromakodi.pdfIn PDF document text
    • http://fapannimario.it/userfiles/files/92834088169.pdfIn PDF document text
    • http://cosyromania.com/media/file/51944678223.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/62771618099.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c10d590b10---jadakavuvatasuvojal.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/61085524209.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/470ba1e1542d87defb0e6c266e7cb8ce/94452709306.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/ruxuvivi.pdfIn PDF document text
    • https://livewireeventz.com/userfiles/file/59153704888.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/69612094590.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/btdogrj6780um69frae2tpbukq/wulawubafox.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/68108100182.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/tusopefotedimazar.pdfIn PDF document text
    • https://steammining.com/userfiles/file/5635220910.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/7472006515.pdfIn PDF document text
    • http://cristal-in.fr/userfiles/file/82297848177.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=amerihealth+caritas+louisiana+provider+manualPDF 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_off0000e76a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76A 10924 bytes
SHA-256: b3c5bcffd3f784821f5b1ceb9a9282b8f2659b5d081b268845a8cfa260a152b9
font_01_sfnt_off0001008a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1008A 20384 bytes
SHA-256: e008561398dee305c414578e58377affc62182dcff33939ca0758801da7f135d
font_02_sfnt_off00013530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13530 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.