Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c1cc1cb994ac79a…

MALICIOUS

PDF

87.0 KB Created: 2021-09-18 20:08:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 79c3abcbe6376dfe8d96ff0009be1bae SHA-1: 4e589ff4ef94595e224c444911154f78b9997c4a SHA-256: 1c1cc1cb994ac79a4a48ab90cecd2f8510945b2bf6d73049f3d36f449cea922c
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. Heuristics reveal it functions as a link farm, with numerous external URLs pointing to potentially compromised or disposable hosting. The primary purpose appears to be directing users to malicious content, likely for phishing or malware delivery, aligning with spearphishing attachment and malicious link tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://tractortools.cz/ckfinder/userfiles/files/29121619580.pdf In PDF document text
    • http://ohdiabo.net/images/ckeditor/files/67596605919.pdfIn PDF document text
    • http://lindendirect.com/ckfinder/userfiles/files/22160105543.pdfIn PDF document text
    • http://www.gpe-el.pro/ckfinder/userfiles/files/vivavewamika.pdfIn PDF document text
    • http://sakurahoaanhdao.com/webroot/img/files/finoxoz.pdfIn PDF document text
    • https://ikuseikyokai.jp/ckmedia/files/mifuveduba.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/mudaxa.pdfIn PDF document text
    • http://dreamwith.gni.kr/ckupload/files/mofigosudez.pdfIn PDF document text
    • https://istanajp2.com/contents/files/wejidofujuvajajere.pdfIn PDF document text
    • http://safarang.com/basefile/files/ravadi.pdfIn PDF document text
    • https://newdesert.pl/userfiles/file/25523134885.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/c232c0831a9fa5d44fea63158d4d657d/32227714536.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/55103185095.pdfIn PDF document text
    • http://szm.hu/userfiles/file/77904611128.pdfIn PDF document text
    • http://sonarkella.com/userfiles/file/wowituf.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/12721151649.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16136edefe3b3b---81482597288.pdfIn PDF document text
    • https://ln80.cn/filespath/files/20210913161341.pdfIn PDF document text
    • http://pphu-joanna.pl/fckpliki/file/pejipoxabugegadojub.pdfIn PDF document text
    • http://casaledellasignora.it/userfiles/files/bevumodevagadazidiredu.pdfIn PDF document text
    • http://autoscuolecasetta.it/userfiles/files/95062568518.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16133e271b936c---bomofuvesezujozetonatemid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=where+to+stream+promising+young+woman+moviePDF 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_off0000eda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA4 11012 bytes
SHA-256: e2c083e3c0baaeb447ef3f4b29391f725fef176b2b0b39279e9a99bbd51e97b8
font_01_sfnt_off00010733.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10733 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F45 18244 bytes
SHA-256: c951858d0939df370a4e149e62e21099735070ecad29176b0649d6ee2df069ce