Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e17cd51b65c4f61…

MALICIOUS

PDF

80.0 KB Created: 2021-09-20 11:58:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 161ff3c3198c9570d41fa1062b5fc8cf SHA-1: 810c2c384aa9918989670f7bf4944bace40d9424 SHA-256: 4e17cd51b65c4f61bd992ccb9101155b545643a06b97d29a380adbbd67d1eb66
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://philabc.ru/uplcv?utm_term=grid+for+instagram+apk PDF link annotation
    • http://huerural.com/uploads/image/files/bipinutupejomenida.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/161483d8daa748---12384741725.pdfIn PDF document text
    • http://maulich.vn/attachment/files/75772548612.pdfIn PDF document text
    • http://theponghop.com/upload/files/30715144770.pdfIn PDF document text
    • https://akproauto.net/nbloom/fckuploads/file/juwarasiponavokavames.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/91855916189.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/161376d3dd9ad9---65124495310.pdfIn PDF document text
    • https://hunghiephuylog.com/upload/files/sawekozusesegavuv.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147f85a90093---dowusinodar.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/palatosutasuxenunup.pdfIn PDF document text
    • http://tumwebthailand.com/ckfinder/userfiles/files/josadogujot.pdfIn PDF document text
    • http://zelene-centrum.cz/webpagebuilder/ckfinder/userfiles/files/34310904430.pdfIn PDF document text
    • http://valencia.thepokeluau.com/uploads/files/20538856227.pdfIn PDF document text
    • https://stop-remont.ru/ckfinder/userfiles/files/98659311636.pdfIn PDF document text
    • https://qfuse.it/images/uploaded_files/ckfinder/files/1631310215_4c6c11a20b.pdfIn PDF document text
    • https://agriturismoilcolle.org/userfiles/file/jaranivav.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147f8aa50c03---97990821117.pdfIn PDF document text
    • https://gmt-tw.com/app/webroot/userfiles/files/lamepawanopegov.pdfIn PDF document text
    • http://www.miyadenthai.com/image/upload/File/noxegiludevekodubu.pdfIn PDF document text
    • http://xn--12cmi2byac9cdhd0hra6d7bxkwbgj1gch.com/user_img/files/23073192083.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/sarisaki.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_off0000d3eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ebfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBFD 17524 bytes
SHA-256: ddcbd7e72eddce85f60509318b2d556d6ba76891477f144192adbde4f8dd4548
font_02_sfnt_off00011a0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A0A 10796 bytes
SHA-256: eaa1e84bc451f005b02cec1c9ea5853870b1c77a5fece80a49ce0e12c6431fe8