Malicious PDF — malware analysis report

Static analysis result for SHA-256 d313c635ee539efe…

MALICIOUS

PDF

68.8 KB Created: 2021-10-01 10:09:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a302058ee94799a792b218ca8896637d SHA-1: a8cc828523507a04c82793f8a2f1cd2524a1c509 SHA-256: d313c635ee539efe2620b9fa4428067d8e049c5c6130f01e6af4a89cdd7834c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be part of link farms or compromised CMS uploads. The presence of these URLs suggests the document is designed to redirect users to malicious sites, likely for phishing or to download further malware. No scripts were extracted, but the PDF structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://oniceh.ru/uplcv?utm_term=w3schools+html+tutorial+pdf+free+download PDF link annotation
    • http://tksvolga.ru/userfiles/file/43663354136.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/72166681595.pdfIn PDF document text
    • https://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/vefogupixuwuse.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613af2e6465c5---vitomoxefupawobesulajef.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/76642883541.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/jerukusifudafu.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/tufezememunez.pdfIn PDF document text
    • https://1tlstar.com/storage/uploads/files/losot.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614732cbcc84c---98071749738.pdfIn PDF document text
    • http://thietbiytedaibao.com/media/files/99151551372.pdfIn PDF document text
    • https://majubesar.org/contents/files/lijebamanozevogolibive.pdfIn PDF document text
    • http://philipsphotographystudio.com/68679517228.pdfIn PDF document text
    • https://funbugs.ie/files/file/satotawati.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/27110776365.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613493ed54fab---27963656528.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149aff04be2e---46400610328.pdfIn PDF document text
    • http://video-cycling.de/files/file/99663386409.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zobolot.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/vinilunit.pdfIn PDF document text
    • https://dorfadvertising.com/ckfinder/userfiles/files/22000440423.pdfIn PDF document text
    • http://elfast.ru/userfiles/file/29657573906.pdfIn PDF document text
    • http://kcpsystem.com/userData/board/file/dunabaniba.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_off0000ad1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD1C 11236 bytes
SHA-256: c6cc7aca594e915b56b304b7a5fb9fef3e18158cbfd05afe289ea8a2bb12dc2f
font_01_sfnt_off0000c75a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC75A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000df6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6C 15052 bytes
SHA-256: 01ff7c9c658bbc62d59d5911ab5573758ef918962987f88dd9c0107c0e7be07e