Malicious PDF — malware analysis report

Static analysis result for SHA-256 c15283b3a2a29838…

MALICIOUS

PDF

79.3 KB Created: 2021-09-18 01:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 2216481338b990a3183144511219add8 SHA-1: 0416a2f83ba736d6f5e0c3d6f42ac0863680da04 SHA-256: c15283b3a2a2983899da8c6f97d5de21b01233c861f089cec9312bc9e440820e
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that point to other PDF files hosted on various websites, many of which appear to be compromised. The heuristic firings indicate this is a link farm, likely used to distribute malicious content or conduct phishing attacks. ClamAV detection and ML classification strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://huntic.ru/uplcv?utm_term=aiscore+pro+apk PDF link annotation
    • http://gizmakina.com/depo/sayfaresim/file/rikumosatugelogixuv.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/82668819565.pdfIn PDF document text
    • http://k3projekt.pl/uploads/userfiles/files/vubuwex.pdfIn PDF document text
    • https://hirurgija.me/files/rodigijufokowow.pdfIn PDF document text
    • http://hzeiger.com/userfiles/file/45135911537.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/59704777887.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161451042196e6---juseguxivu.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/94874456171.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/69410189816.pdfIn PDF document text
    • http://retrolondontees.com/userfiles/file/xolosedimegulo.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file///51134845821.pdfIn PDF document text
    • http://baggiez.net/userfiles/file/50149826843.pdfIn PDF document text
    • https://dcimx.com/files/kivuj.pdfIn PDF document text
    • https://ms2oke.com/contents/files/18561090688.pdfIn PDF document text
    • https://bccphil.paramedix.biz/uploadfiles/file/boxivorimasu.pdfIn PDF document text
    • http://willettelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/78453354889.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613f477967da9---95628229770.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/42936785484.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/161385475acb08---99907664254.pdfIn PDF document text
    • http://naplesredeals.com/userfiles/files/2152430731.pdfIn PDF document text
    • http://xhiehchin.com/Xhieh_News/_file/fivelamajugirivokowanati.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/nizafolikivoxi.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_off0000d063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD063 10192 bytes
SHA-256: 9b2e4b17b9406432f9e97f4fc76b64907443fc798ca55ed1124f21ae9944196e
font_01_sfnt_off0000e764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE764 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF76 18544 bytes
SHA-256: a5f9d44a0c0f50d8768de82e2c53fd5a5c5c524710483c846396a8ce236b47a9