Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb65b86dad8abe44…

MALICIOUS

PDF

81.9 KB Created: 2021-09-13 01:13:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4a861973f9a8b270f993256ee6274306 SHA-1: db70155fc291581b227b31b94d9e5f87e63f5b86 SHA-256: cb65b86dad8abe44ae8ff38fe14a82ae1b5ac9b70f84b0464f2984cf41c84d47
164 Risk Score

Malware Insights

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

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 external URLs, some hosted on compromised CMS platforms. The presence of a 'download button' lure further supports a phishing or malware distribution intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://garglob.ru/uplcv?utm_term=mod+apk+clash+royale+hack PDF link annotation
    • https://hoalavender.net/upload/files/jomaw.pdfIn PDF document text
    • https://eventpro-kontraktorpameran.com/uploaded/files/nuzariroselivuleworak.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/zufegunefupu.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/zajusizavuxifidubobaruku.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/98aa0a61837722f70b8fed7431494c49/51253948729.pdfIn PDF document text
    • https://eminentland.com/admin/userfiles/files/peminebexabujibikaditiz.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/vepiferer.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/dolasinikepa.pdfIn PDF document text
    • http://stylekd.ru/files/fenelinomizegerigulotuwi.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/lumilopilad.pdfIn PDF document text
    • https://hatinhjobs.com/upload/files/40388105302.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/676e76203d19b118d2fcfdc020d2b8ae/puvuxozowuti.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/xoveboxuwowa.pdfIn PDF document text
    • http://minhtoangalaxyhotel.vn/app/webroot/files/ckfinder/files/66175180504.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/20607370310.pdfIn PDF document text
    • http://premiercontractinginc.com/files/file/90851170202.pdfIn PDF document text
    • http://inteko-tula.ru/f/file/47370540572.pdfIn PDF document text
    • http://veterinariacasettamattei.it/userfiles/files/75985743473.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/96154136928.pdfIn PDF document text
    • http://artetendasud.it/userfiles/files/16882886446.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135d8a9795e1---37168612576.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139975f75994---51650318127.pdfIn PDF document text
    • https://lean-ds.com/upload/editor/file/xepijagebobodeveparofa.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/63678043442.pdfIn PDF document text
    • http://antifftech.com/uploadfile/file///2021090410581016.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/92786848620.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_off0000da8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A0 18340 bytes
SHA-256: ef9917efcd153b5e3523bffa3c210b88e8f6021f088e0316fc7f7ab4e061a1e0
font_02_sfnt_off00012231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12231 10516 bytes
SHA-256: fe9ea22980cb991e8eccbf0a95a65f0236d8b683b03e771ab41ab533dc9bd2d2