Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4938bbb38fec3fc…

MALICIOUS

PDF

79.8 KB Created: 2021-09-09 18:13:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 495434ba7e3ab5f3c677e41fa04bba7e SHA-1: 8c08db966b71204133892e9ae187fc4de4b26657 SHA-256: e4938bbb38fec3fc99d6d19124f4e477827b9303d09c8392c3c9c6befa3d9406
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains. Heuristics indicate this is a link farm, likely intended to lure users into downloading malicious content or visiting phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://ketchas.ru/uplcv?utm_term=kof+mugen+apk+obb PDF link annotation
    • https://medarbindia.org/ckfinder/userfiles/files/nagesa.pdfIn PDF document text
    • http://sapthagireesyathra.com/userfiles/file/61395316211.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/98635662600.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612feba3c317d---xalunavenololaw.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/haeu34eqo9c0heie4jnuuc8r0r/657966417.pdfIn PDF document text
    • https://medpressa.ru/files/file/moputiraruba.pdfIn PDF document text
    • http://tianlanlawyer.com/filespath/files/20210902142441.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/taxafenitigixomumigabukef.pdfIn PDF document text
    • https://kokomanis.com/contents/files/24649173109.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/nifusesoxomunadolilije.pdfIn PDF document text
    • http://nbc.ua/design/pic/file/19551411244.pdfIn PDF document text
    • http://theloanwala.com/userfiles/file/jelipe.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/nujufizut.pdfIn PDF document text
    • http://e-district.org/userfiles/file/kevevosowimozaga.pdfIn PDF document text
    • http://rococosofa.com/files/files/dovogujotoza.pdfIn PDF document text
    • https://network-italia.it/file/51775500784.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/8gjcqvtrfdtpalprk00u96bi73/43271852685.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/taxajan.pdfIn PDF document text
    • http://rkmaster.ru/uploads/files/98294381724.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/33797756589.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/66563944449.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133a4b7a2420---wepobotalukowosirof.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/wagivukuba.pdfIn PDF document text
    • https://www.thic.net/plugin/ce1/ckfinder/userfiles/files/josudukinabobasolixe.pdfIn PDF document text
    • https://greenboo.vn/uploads/files/95864468133.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://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_off0000d2a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2A0 10520 bytes
SHA-256: 6be3583a6d241beab65e535d5c023eece4f84e8682684b9c0248928819b72471
font_01_sfnt_off0000ea55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010267.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10267 17988 bytes
SHA-256: f2e9666e2f815daae0da6d2b50fc430623d425a0db763d4f16878e4ca0a2a403