Malicious PDF — malware analysis report

Static analysis result for SHA-256 082383c5ca4c7795…

MALICIOUS

PDF

74.4 KB Created: 2021-09-20 15:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 71e137cfb1aa4dd6d28bedf9b7e277e9 SHA-1: c1c83b486bf0772d4e23d78bcbb08cfbda8e1ec9 SHA-256: 082383c5ca4c7795c9febd11626fe966ca8e1b959f5c112692ce51dc9d06d13c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers 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 potentially compromised WordPress sites. The presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 https://laborke.ru/uplcv?utm_term=my+stupid+boss+full+movie+lk21 PDF link annotation
    • http://eatatrudy.com/uploads/files/fozafapobamo.pdfIn PDF document text
    • http://ptsound.com/plugins/ckfinder/userfiles/files/62623797820.pdfIn PDF document text
    • https://weilaimachinery.com/userfiles/files/32555820245.pdfIn PDF document text
    • http://elskenecologie.nl/files/81896027980.pdfIn PDF document text
    • http://td-mg.ru/uploads/files/dakutizuwawagegisun.pdfIn PDF document text
    • http://dailymaydemtien.com/userfiles/files/boguwafedasorulix.pdfIn PDF document text
    • http://inistor.com/ufiles/files/vedobupezato.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/files/povitiremukagawogamutig.pdfIn PDF document text
    • https://kolegium.inaheart.org/upload/files/nofizagovaj.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161438e5b8009b---63132660487.pdfIn PDF document text
    • http://osc-pribor.ru/products_pictures/file/38067257811.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/35836266521.pdfIn PDF document text
    • http://vetusmeter.com/images/upload/File/43900422299.pdfIn PDF document text
    • https://tnmkor.com/FileData/ckfinder/files/20210901_2AFE16AF6B5741B3.pdfIn PDF document text
    • http://life-worldwide.org/assets/uploads/files/sigazarapasabikoju.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/7975110323.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/29801905728.pdfIn PDF document text
    • http://rintoyo.com/userfiles/file/41578237426.pdfIn PDF document text
    • http://www.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe1861cc66---56631385100.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613376a2772c2---borafikibezusorusew.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16144e42d49028---mafedorozorimokulazu.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/6026950631.pdfIn PDF document text
    • https://support-trevianum.nl/userfiles/files/jegijesizagijegu.pdfIn PDF document text
    • http://exms.fr/sites/default/files/file/70760078037.pdfIn PDF document text
    • http://artsar.pl/userfiles/file/xugijenanapuwasu.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/vonilegosulorosemepevitej.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_off0000c051.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC051 10972 bytes
SHA-256: d49cf3b525aec7b3215d129579e6ec7c3e21c35c484688604d4c3282ac63d2b4
font_01_sfnt_off0000d9af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9AF 16324 bytes
SHA-256: 8dcea5f42eff81a07d7710cf23feeeec0b14b12e3683dae73940930a1c28584c
font_02_sfnt_off00010396.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10396 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1