Malicious PDF — malware analysis report

Static analysis result for SHA-256 e16113ca99f50139…

MALICIOUS

PDF

74.4 KB Created: 2021-09-08 06:14:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7e9f05783507627ae765bc2127f16688 SHA-1: a54fe728692f88e60c92c7d37140860e95ad5395 SHA-256: e16113ca99f501399191a08d7fbef7e23e541333ab7ba00af90565f3b095892d
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites. These sites, in turn, host other PDF files, suggesting a multi-stage distribution or phishing scheme. The presence of multiple distinct hosts and the use of compromised upload directories indicate an effort to obscure the true origin and purpose of the malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • 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.
  • 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://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160853ff17197b---gafafereduzekikojuforur.pdf In PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16082327cbe079---58723125527.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608dbb7dae913---jejetilugatilunusubiv.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a863c7a4f40---95927054978.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a64b3ff3e36---44827664933.pdfIn PDF document text
    • http://peusch.lu/userfiles/files/vubilutiwule.pdfIn PDF document text
    • https://vientangluc.com/upload/files/wavuxutenoxojo.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9b0dab0f71---91020816285.pdfIn PDF document text
    • http://quadocdao.vn/uploads/files/63999368943.pdfIn PDF document text
    • https://gulceoyunlar.com/calisma2/files/uploads/73228514156.pdfIn PDF document text
    • https://ficsllc.com/wp-content/plugins/super-forms/uploads/php/files/k3rok23gati6unpmrld8n94k61/debewovofalevipeleb.pdfIn PDF document text
    • http://zsmnowakowski.pl/userfiles/file/dukazigekiluxor.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/ragew.pdfIn PDF document text
    • http://vrajacreation.com/uploaded_files/userfiles/files/tepatat.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/82af87221ef8fc727f5dd75a39bab74a/nopewatiguwefiko.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/vurejurebepiwogokipuna.pdfIn PDF document text
    • http://djarkitek.com/temp/vinney/HTML/userfiles/file/89837166723.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/29b0790c4e43178cb8f76c8553801c53/73251281194.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/76870033105.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/nexezajile.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160dc909a6adce---tozijexuwarigewamiveg.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f50a09cfcc---6033153362.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/118dda55ea75d05bffef115590254094/69621672618.pdfIn PDF document text
    • https://people11people.gr/uploads/File/ridamifoxakipedidesutudu.pdfIn PDF document text
    • http://skisun.it/userfiles/files/21908980366.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=manual+radio+pioneer+mosfet+50wx4+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_off0000bc66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC66 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD478 17320 bytes
SHA-256: 91759428378dd2fef2dd40ddf39d4d2a3512f74bfbdf31d7ff45f2e81bb59106
font_02_sfnt_off00010126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10126 11276 bytes
SHA-256: 1eac1c0376f1d1b48c5c69a96242686c0a8705ee09cfd71c8d876772d4dc49f7