Malicious PDF — malware analysis report

Static analysis result for SHA-256 cad6f02869b99332…

MALICIOUS

PDF

88.4 KB Created: 2021-09-13 03:20:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4ebf15c4d9cf0539d08df86054c4e771 SHA-1: cb59e00557b06f0b7251540a9358cda7f08ac777 SHA-256: cad6f02869b9933238c174ba967f7af4056e07e51779e4a9a8bcbee40e757e41
212 Risk Score

Malware Insights

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

The PDF contains an embedded JavaScript stream and multiple links pointing to external PDFs hosted on compromised WordPress sites and disposable domains. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a deliberate attempt to distribute malicious content through a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to deliver a phishing lure or a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 9

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://medvor.ru/uplcv?utm_term=wwe+hack+apk PDF link annotation
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/rexalop.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/c79e177fe3d2f06b3597289ec9d9ef11/57387705992.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/12054520645.pdfIn PDF document text
    • https://tailormade-sales-marketing.com/userfiles/file/xekivujugap.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/gofofobid.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/96965941694.pdfIn PDF document text
    • https://somogyplusz.hu/files/34869326020.pdfIn PDF document text
    • http://revize-elektro.info/UserFiles/File/63471732842.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210911190455.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/wadepi.pdfIn PDF document text
    • http://peach2560.xyz/js/ckfinder/userfiles/files/94337590458.pdfIn PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/dapinunol.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/52211170639.pdfIn PDF document text
    • https://shop-ecobati.com/medias/upload/files/13390614742.pdfIn PDF document text
    • https://copperscrap.wasteequipment.net/ckfinder/userfiles/files/41944912781.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5b7d630f9---molomajivutokiso.pdfIn PDF document text
    • http://maudchristan.nl/ckfinder/userfiles/files/bakun.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/d3va1a4qqffneecag2p2eh3mvv/66110902757.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/53300074797.pdfIn PDF document text
    • https://www.edm-medical.net/ckfinder/userfiles/files/vivizapozozu.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/84434833083.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/c4e53a50e3f3f0340e5c606ddbd6b367/33631521750.pdfIn PDF document text
    • http://restavracia02.com/userfiles/file/36820340159.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/28589214596.pdfIn PDF document text
    • http://naturenhuman.com/app/webroot/userfiles/file/85601457629.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/miwutosof.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_off0000f40e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40E 18960 bytes
SHA-256: a0dfdf6c3ba61396a3c45236515ae320cd0796686c600360f49f73acce7bdb07
font_01_sfnt_off000125d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125D9 9916 bytes
SHA-256: a7c9b5d715dc89a98d747ab4dabae1866d9856a3d038292c9d005ec94d568f0c
font_02_sfnt_off00013bf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1