Malicious PDF — malware analysis report

Static analysis result for SHA-256 dba08f2a22077a89…

MALICIOUS

PDF

73.1 KB Created: 2021-09-15 17:18:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3f147309673a723979c039428230dce2 SHA-1: 939ae379d328549acc58446d58db8d41cf7207fc SHA-256: dba08f2a22077a89074a09b551c7fd6d4d5d19400481c2f0b411fdd41c409e56
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS upload storage or disposable hosting. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics strongly suggests a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://longruiglass.com/ckfinder/userfiles/files/20210903_042715.pdf In PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/15560373359.pdfIn PDF document text
    • http://12shio2.com/contents/files/tatazarejufib.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/gilerunifasagowet.pdfIn PDF document text
    • http://pawsandtiaras.com/ckfinder/userfiles/files/4806778099.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16133fdfea9a64---11134559681.pdfIn PDF document text
    • http://predit.ru/admin/ckfinder/userfiles/files/8141637333.pdfIn PDF document text
    • http://struttur-arch.it/userfiles/files/51645798338.pdfIn PDF document text
    • https://funcarele.com/ckfinder/userfiles/files/ninarufok.pdfIn PDF document text
    • https://tigaintan.com/contents/files/57045722970.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139f4bde5750---17170985213.pdfIn PDF document text
    • https://tempatpasang.com/contents/files/99535174492.pdfIn PDF document text
    • http://szcftz.com/upload/78708201676.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/24333225077.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/sitazi.pdfIn PDF document text
    • http://xy-interior.com/uploads/files/202109132301229447.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5fcb1b891---69861882714.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc757b196b---tukobaxopupujitun.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/l436c32sboneba40p5oso246to/63627256654.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/74120440758.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/mukegovekekopudemabizora.pdfIn PDF document text
    • http://hypotekaprezamestnancov.sk/res/file/24921532457.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/3708434149.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=pokemon+remake+androidPDF 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_off0000b6dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cef4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEF4 10192 bytes
SHA-256: b05f44380a32d5c0fad61ecc1d01d14b9baab66b4e37714b564213d8b4f3a6b4
font_02_sfnt_off0000e5af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5AF 19228 bytes
SHA-256: 9bc5b929efa6f49831be06a5a28638074c1dff7f20154437c1cecfe8f5e9703e