Malicious PDF — malware analysis report

Static analysis result for SHA-256 143cdc1de636761a…

MALICIOUS

PDF

80.7 KB Created: 2021-09-15 21:51:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1bab7e2d22bd5866f2ab211a7d73d51d SHA-1: 8be7138d66b2f79e2b4849f0110d661ee194598c SHA-256: 143cdc1de636761a467e3483849367b05b5be9bdbcf58cd4202d9a1b6df6d73a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised websites, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a phishing lure designed to trick users into downloading further 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 http://wmasgroup.com/userfiles/file/fanikolesebaloruzevirunon.pdf In PDF document text
    • http://epoptavky.com/is/images/FCKeditor/File/wixotokovitozolusakib.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/tapel.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/muwanajav.pdfIn PDF document text
    • http://aallergy.friend-match.com/upload/files/38538543547.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/4d70f9faf7da91fc04f9e1f757930ebc/fesibinunurajikufelagew.pdfIn PDF document text
    • https://swift-tw.com/lcc/upload/files/75108614650.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/e29fc3e50a5413f8d090535e5128faac/zitodovezix.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/pesedijulozaxo.pdfIn PDF document text
    • http://leylasuren.com/images/userfiles/imagefile/35044917681.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/79537041575.pdfIn PDF document text
    • https://1877painters.com/FCKeditor/file/jegogikotijekefagi.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/75113973930.pdfIn PDF document text
    • http://momsystem.ru/public/file/22965434443.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/t1njpaqoad19b95uik6qtlush2/91925374404.pdfIn PDF document text
    • https://propage.q-cloud.net/upload/ckeditor/pages/files/14369140656.pdfIn PDF document text
    • https://primer-spb.ru/files/files/xilidovutulofedinumil.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139147247ebe---55131747127.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/161406428bc6e3---sititomevasanubi.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/54563934882.pdfIn PDF document text
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/sovevide.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=free+download+mx+player+proPDF 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_off0000d75d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF74 10472 bytes
SHA-256: 31d1958e78fdade861217d6e8028be0c875d8d3d41933cb9635720d53cc96a07
font_02_sfnt_off00010738.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10738 17976 bytes
SHA-256: f6c9af734568324e6fad12ed819d535d237195eef0eeb1ed12395c31a3dc43fe