Malicious PDF — malware analysis report

Static analysis result for SHA-256 de873d8919120ee3…

MALICIOUS

PDF

83.6 KB Created: 2021-09-16 20:30:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9e3c85656d85977fd978ce8f5347c28d SHA-1: c8db441da699ec293c28a69abc3c099d310cdac3 SHA-256: de873d8919120ee336935c705d4ff68e1f612fbadaf07ca3fa918c558b4110f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to compromised WordPress upload directories or are hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to distribute further malware or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://synerhu.ru/uplcv?utm_term=download+video+fx+for+android PDF link annotation
    • http://loscogliodifavignana.it/userfiles/files/90793136303.pdfIn PDF document text
    • http://studiodispirito.it/userfiles/file/51757127926.pdfIn PDF document text
    • https://cpsguffanti.it/uploads/file/80895089893.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/6560240352.pdfIn PDF document text
    • http://myphamso1.net/uploads/files/5276197804.pdfIn PDF document text
    • http://stagticket.com/fck_upload/file/73967329068.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140143d00124---sododitifunodalirozogejo.pdfIn PDF document text
    • https://warungmimpishio2.com/contents/files/5181879586.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/rawasumugo.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/29335916373.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/25750346252.pdfIn PDF document text
    • http://eclickapps.in/userfiles/files/bajibuzeje.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/gawedevejegozumivituroro.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/debelij.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/18535065540.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613740b4923ce---92735130318.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16138f0bbae9b6---94609611824.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/51951485007.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139d052a7ea6---63259571333.pdfIn PDF document text
    • https://ms2gacor.com/contents/files/xigefadebixad.pdfIn PDF document text
    • http://globalnetworks.de/www.galabau-poscher.de/main/preview/ckfinder/userfiles/files/11411074876.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/zubaxulilu.pdfIn PDF document text
    • http://kelt.pl/userfiles/file/joloke.pdfIn PDF document text
    • https://unitedfightalliance.com/ckfinder/userfiles/files/rerewetodap.pdfIn PDF document text
    • http://autolavaggiocraparotta.it/userfiles/files/50309679246.pdfIn PDF document text
    • http://mcserpenti.com/userfiles/file/97995458814.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_off0000e4dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fcee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEE 17256 bytes
SHA-256: 4c68bdcf46ebbdb4dd5de408356a1b92d571f3b57b2614a93ab49b2f461f947f
font_02_sfnt_off00012925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12925 10336 bytes
SHA-256: f39d1b0ecf9bff31ea605e3ba5ecfccd3f389b9b5a5dbb051047f532a8c4aff9