Malicious PDF — malware analysis report

Static analysis result for SHA-256 bbca8275526297e9…

MALICIOUS

PDF

80.1 KB Created: 2021-09-21 08:50:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 13276a7d5cfe1b0dd1874844d60b9db5 SHA-1: 7fe1506cc0db062a5e7efe5bf9bf750f6d912f2f SHA-256: bbca8275526297e95a717b76fc4c209209e7c1538e89d93604175f616dd6efb4
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress sites and other disposable hosting domains, likely for phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to exploit users by luring them to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://laborke.ru/uplcv?utm_term=how+to+block+a+number+on+android+kitkat PDF link annotation
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16141fd665a37f---96438830658.pdfIn PDF document text
    • http://thewellmanteam.com/userfiles/files/xibezijosematapaburoj.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/4fb54c92e1a51bed78ccb33759530dd9/zevojovogiwane.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/sexewevawez.pdfIn PDF document text
    • http://gibisch.com/files/files/zolumozuvek.pdfIn PDF document text
    • http://air-con.ru/upload/files/48573939262.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/77b8b4a2b096fd72003774b0c881ee14/4804841545.pdfIn PDF document text
    • http://gsprojekt.eu/userfiles/files/38160200620.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/obd2f4hjtp2t2r1nak6dradt1g/67135783056.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/safuxa.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/tutinovegizixogu.pdfIn PDF document text
    • http://bongoes62.dk/userfiles/file/vigakigifigoba.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/31348851836.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161452259ab9b4---jifutawikifotu.pdfIn PDF document text
    • https://volpatoebrum.com.br/_common/admin/scripts/ckfinder/userfiles/files/lisuvupivuwo.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/20998895307.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/1050031267.pdfIn PDF document text
    • https://www.nstoplana.rs/ckfinder/userfiles/files/pomofonigekuwe.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/16695998370.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/pojufimuvipumum.pdfIn PDF document text
    • http://agrostroi-proekt.ru/ckfinder/userfiles/files/kisalamej.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_off0000d44e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD44E 17736 bytes
SHA-256: 5b221ba3c80ab4f189235d1a71a87c732b3c87d312d02d9d39937632dcaf7a2d
font_01_sfnt_off000101d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D6 10772 bytes
SHA-256: 6cd69773ed980a41dd87c38a5138ac7f6c7020667e3af95c70572184a1dddef5
font_02_sfnt_off00011a9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A9C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1