Malicious PDF — malware analysis report

Static analysis result for SHA-256 773f4f031665296c…

MALICIOUS

PDF

81.2 KB Created: 2021-09-18 16:07:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 832078a77c3af8149765fa95afe20cf7 SHA-1: cbce92e4f289efaf4373158ac94d218046f2717d SHA-256: 773f4f031665296c34e34e4c31d399aa2fa2a666d049d463b24e2ef1778af29e
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of numerous links, including one with a 'utm_term' parameter suggesting tracking, points towards an attempt to direct users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://spartapr.com/images/upload/file/88915510319.pdf In PDF document text
    • http://starma.pl/files/file/nozazudoxanaderijevajiza.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/e6487072aa053c741e60dc14e9e17feb/89182448102.pdfIn PDF document text
    • http://vibrobreaker.com/files/files/lumuvusoxepofajujuriri.pdfIn PDF document text
    • http://woykoff.hu/upload/file/gupuzowobapo.pdfIn PDF document text
    • https://ukmalayalamnews.com/userfiles/file/rudufupaxurowax.pdfIn PDF document text
    • http://pnlestari.com/visitbali/image/files/kekikofo.pdfIn PDF document text
    • https://joinvita.com/neu/userfiles/file/61559069666.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d84044cb8c---77268075290.pdfIn PDF document text
    • http://delfosventures.com/userfiles/files/40953152554.pdfIn PDF document text
    • http://firewaterdamagedfw.com/test/fckeditor/uploadfiles/file/wovorisaditerepeno.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614210bccc3ea---sowarozunubexodup.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/xajomepezomutufeligumi.pdfIn PDF document text
    • https://aucordechasse.fr/vosImages/pijekozolunotigalagogip.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/3a3eadp17n333t6out5dkr20g4/wuxubuxuj.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/dupoxexalemomujumido.pdfIn PDF document text
    • https://phukienbep.net/media/files/bugexunojizigisuge.pdfIn PDF document text
    • http://inbeeldt.nl/userfiles/file/64703241592.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/fezowesoxuwunixosa.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/43962637949.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/58951241546.pdfIn PDF document text
    • https://photojet.bg/userfiles/file/57603152182.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=mod+apk+among+us+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_off0000dae6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE6 10644 bytes
SHA-256: 92b22d8240e04bcd76038693b9638e03161fccaa9824044c53c76f58767d3144
font_01_sfnt_off0000f2f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B08 17180 bytes
SHA-256: c18addfd332539ad2f89fcc1dfeae33fb73fdaf5bdd8b1cb83a593fbaac7e14f