Malicious PDF — malware analysis report

Static analysis result for SHA-256 7e2ea25ab8e036b4…

MALICIOUS

PDF

84.7 KB Created: 2021-09-10 03:04:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d99f5865f5b28624501cf7485cd3ef24 SHA-1: 1d75f3be924a90403437323826d80c1827895515 SHA-256: 7e2ea25ab8e036b4408b23d1b9ffb7d2fd7bbdaf2154284afba811311037b7ad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple URLs extracted point to PDF files hosted on various domains, some of which are flagged as potentially compromised CMS uploads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user consumption but rather as a container for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://hongdacable.com/d/files/79964713218.pdf In PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/rovirije.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130008f8f605---wotirutedex.pdfIn PDF document text
    • http://wine-paraphernalia.com/files/winep/_repo/file/nomeru.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/bizivuwogurofud.pdfIn PDF document text
    • http://digitalpolicycouncil.org/imagenes/file/sorurefibafisotab.pdfIn PDF document text
    • http://duocmyphamcongty.com/app/webroot/uploads/files/lutakob.pdfIn PDF document text
    • http://perfect-gallery.com/userfiles/file/xolefimujezuwapeko.pdfIn PDF document text
    • http://malagi.pl/user-files/fck/file/22374817608.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/xisaridemutupijufuw.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f73fe7f333---fuxizoxizufowujogimi.pdfIn PDF document text
    • http://restavratorstvo.com/ckfinder/userfiles/files/52661697183.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/tafile.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/ca024ee493722a22c5821213709d5e9e/4719990918.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/letumepas.pdfIn PDF document text
    • http://marketingnews.fr/images/file/18314291919.pdfIn PDF document text
    • http://tchid.net/userfiles/file/90727933717.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/mebibimetoxunotonavakajol.pdfIn PDF document text
    • http://tdvvietnam.vn/webroot/img/files/73765756925.pdfIn PDF document text
    • http://phamtrangia.site/upload/files/ketasime.pdfIn PDF document text
    • http://vongtaygiay.net/media/ftp/file/5425200088.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/jedulugepemeruziwexasi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=android+equivalent+of+imessagePDF 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_off0000e5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD8 17828 bytes
SHA-256: 0d3b852101258972409d1f8d30abd5695d31cc9f763875338c69d33c1b3f98ef
font_02_sfnt_off00012c5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C5F 10988 bytes
SHA-256: 75491a3a65a4068fdcacb0607d20ea5511838ba57fca4091b08548565ccebacc