Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb10a586eab3b3ed…

MALICIOUS

PDF

80.1 KB Created: 2021-09-11 16:47:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 2104734f0364020d52f22ccce969070b SHA-1: db2319db182af45e98b8059c1e9abb17e9c07fb8 SHA-256: cb10a586eab3b3ede7a6a19a08fed6841e61a4cf173655f54004ac26d695be97
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress upload directories. The primary purpose appears to be directing users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://blevy.com/ckfinder/userfiles/files/piliba.pdf In PDF document text
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/56904815081.pdfIn PDF document text
    • https://www.verimevzabavu.cz/ckfinder/userfiles/files/suderavapugepi.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336cc102438---72562382326.pdfIn PDF document text
    • https://dacola.com/upload/files/8229749465.pdfIn PDF document text
    • http://truhlarstvi-strakonice.cz/files/file/67027150042.pdfIn PDF document text
    • http://seasonmediagroup.com/pic/file/nutotokuneg.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/96608834364.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42304955616.pdfIn PDF document text
    • http://essentielles-theater.de/UserFiles/File/43169150564.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/26936535138.pdfIn PDF document text
    • http://cheliabinsk.realxenon.ru/uploads/files/tutubawagefexujisariniwe.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16134ab34ce5a0---rubegimagojefubimofowo.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/18251887736132f22ac8337.pdfIn PDF document text
    • http://zhjpharm.com/upload/files/85416743969.pdfIn PDF document text
    • https://2acontractor.it/images/file/lumab.pdfIn PDF document text
    • https://nguyenhungstone.com/uploads/image/files/51770613765.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210901170048_uljr4d.pdfIn PDF document text
    • http://gibisch.biz/files/files/37108446148.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/25671275347.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378edf67efe---4279890725.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130c53399dd5---sanajogaluvemi.pdfIn PDF document text
    • http://volkshilfe-vlbg.at/images/content/files/2362903874.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/19973137126.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=block+cars+online+hack+apkPDF 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_off0000d187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD187 18748 bytes
SHA-256: d2b6e0258a2b98fd6e39facacf3950c42de8c58f576f8f08607268fedf6842b9
font_01_sfnt_off000102c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011add.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ADD 10516 bytes
SHA-256: a8d9f7d55b652ddef4d291cbe4ff65672a90e50b3443adf71be76dafcc67ed0e