Malicious PDF — malware analysis report

Static analysis result for SHA-256 231b94f994130e6e…

MALICIOUS

PDF

89.6 KB Created: 2021-07-21 01:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: ee20189fc31d1d1a2ad54dac2a6cc5ae SHA-1: 1f4664845f37c3f626bc5316568eb12a3b2e390b SHA-256: 231b94f994130e6edaf7fc1f88797b39b056e8eed9c7d353ab7dd26799c0b9a7
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to various potentially compromised websites. The presence of multiple PDF link farm indicators suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://2ds-creations.fr/userfiles/file/bisetaj.pdf In PDF document text
    • https://sportsht.com/userfiles/file/fiweguguxenanilaxufo.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/cb99d7cd3fb2db1f733221aeae902162/loloriwejevamubi.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b4dfd162c25---tuvod.pdfIn PDF document text
    • http://archerelectricsupply.com/userfiles/file/dukikuraloluviro.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/kijapajar.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/66ac4a2546af6fea79c2239cf97975b8/63087843092.pdfIn PDF document text
    • https://austarpharma.com/upload/files/73733631851.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16087d9a6a03ac---vanulatatuzat.pdfIn PDF document text
    • http://yer-krasnodar.ru/ckfinder/userfiles/files/68810912708.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/b36ac73a24239b84d01cd3110afe1a93/muvubidutodomelepawizib.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ade3eec97---41617350737.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/mozukes.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/sokamukab.pdfIn PDF document text
    • http://bukharageorgia.com/sites/default/files/file/37486044584.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/wuxex.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/pixoziruxaresunapakap.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/r6l1bprkfb536ertnr66kp8irn/31977250645.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607856bb7e5f4---95677696752.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=request+message+in+messengerPDF 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_off0000fdee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEE 16884 bytes
SHA-256: 5a1479a15f88fbb8d622920480a72544e19dd2002af829d5de09cfb3db901348
font_01_sfnt_off000129a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129A0 10576 bytes
SHA-256: fc371818ed6c881955c70d79989f8d0d6580d370cd3e5ce9b80f0391180eae9b
font_02_sfnt_off0001416b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1416B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1