Malicious PDF — malware analysis report

Static analysis result for SHA-256 dff19077c297a4a0…

MALICIOUS

PDF

70.2 KB Created: 2021-09-18 12:37:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 311151f446e894b63a23a6b99fded41f SHA-1: 8b0259a210c18af57e2242efd0cb9cd9c08dffd4 SHA-256: dff19077c297a4a09a595f4aa074a7ad9393ee633a21fd62eb8fa35376c4800c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external URLs, many hosted on compromised websites, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chcial.ru/uplcv?utm_term=the+world%27s+hardest+video+game PDF link annotation
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/70vlrhu7p1e8b2idnt5p92s81c/3254808416.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b54000a21---giwajuvejegekupipuxoruzid.pdfIn PDF document text
    • https://elsa-daulte.com/ckfinder/userfiles/files/dojosexorufirazepizuf.pdfIn PDF document text
    • http://bidmitt.com/img/files/file/84004786351.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/07850e873784cf6ee9a8b4b292738557/favuvisutawa.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/wifibuxepugerufotiw.pdfIn PDF document text
    • https://architektor.ru/uploads/file/zuwaxizamepitofuf.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/ladazadilojan.pdfIn PDF document text
    • http://autostyle-japan.com/js/upload/files/90960509955.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7c59dc100---19476491214.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/72714059494.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202109010223542164.pdfIn PDF document text
    • http://binhchuachay.info/Images_upload/files/22729960464.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/pekuwejetoj.pdfIn PDF document text
    • https://thebookonpersonaltransformation.com/FCKeditor/file/puxekanorukojanogizerelul.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/ild81kbj8633jo63clqbkdiccv/detupabakogofo.pdfIn PDF document text
    • https://gad-elhak.com/userfiles/file/fudonebe.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcd5716305---66197803680.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/4672513395.pdfIn PDF document text
    • http://shiny-baby.com/fileimage/file/valapomexakekekedojirijo.pdfIn PDF document text
    • http://jyjjapan.jp/files/ckeditor/files/79676658913.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_off0000b351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB351 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB68 10740 bytes
SHA-256: a04dfa43c48e5ff84934061a993bca922ed406d46a66921954ffbead08bc8f78
font_02_sfnt_off0000e401.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE401 15476 bytes
SHA-256: 128b23b75cce1d1086942cb0c6703ca6a910aad2fdd35d6d3b9977af972728c1