Malicious PDF — malware analysis report

Static analysis result for SHA-256 c91f30ac85d343c2…

MALICIOUS

PDF

76.6 KB Created: 2021-09-19 17:08:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 17e7d45ee27e0845afe225ba3aee982d SHA-1: b7d8f4eb5d77beef71c34cb0091652f6b91865c9 SHA-256: c91f30ac85d343c24cd45d7c2229ad04e3c27010de674e4cfa6a34d3ab044c12
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised websites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs indicates a potential phishing or spam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • 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.
  • 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://smidgel.ru/uplcv?utm_term=vidmate+pro+mod+apk PDF link annotation
    • https://lemonsport.sk/upload/file/togokefefewakodosu.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/zofasebopanolikunit.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134db7b53b71---fivotararonenazod.pdfIn PDF document text
    • http://sport-zavora.cz/data/file/lajufisulajibokamowoxipe.pdfIn PDF document text
    • http://24horasnoar.com.br/ckfinder/userfiles/files/36315098056.pdfIn PDF document text
    • http://dent-pro.cz/pic/file/wagowajuke.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/3daedb55434bbc1812a05938e0521e05/85739786716.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d2e219cf58---zudadivudosunavupo.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/87129169119.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/28373877637.pdfIn PDF document text
    • https://scalper.ir/data/files/file/fubalipefupo.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/kelopaxok.pdfIn PDF document text
    • http://shopabrang.com/images/files/figoxosimitebajokuro.pdfIn PDF document text
    • https://betsin.org/userfiles/files/xowinomax.pdfIn PDF document text
    • http://fitsiluet.cz/data/file/sawejobi.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-14-05-01-17-62.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/84190461807.pdfIn PDF document text
    • https://acmfashion.vn/uploads/files/fofibaxuzivinadejukisaz.pdfIn PDF document text
    • https://tl-systems.hu/files/files/81278244858.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134f1f8e6ca9---dijisototuvojuvomi.pdfIn PDF document text
    • http://asja.ua/userfiles/file/91334126556.pdfIn PDF document text
    • https://pracowniatechart.pl/fckpliki/file/48178533967.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_off0000c8ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8FF 10296 bytes
SHA-256: 83795265acb96049330cd9640c904672ca5c9a367262e7a375ca41aa05c2d79a
font_01_sfnt_off0000e02a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE02A 17272 bytes
SHA-256: 4cba69af7c9a0f64cc753c39acfa091c56032675885345aaa6d2d5433602deb4
font_02_sfnt_off00010d29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1