Malicious PDF — malware analysis report

Static analysis result for SHA-256 988253a059e5e75f…

MALICIOUS

PDF

71.8 KB Created: 2021-09-24 11:19:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c9b4610272395424a415c63e2890e5b4 SHA-1: 70c7ae87c6d08b0de204ebbd8ba3609d05bdbca2 SHA-256: 988253a059e5e75fee02b7e863cb58e8aaadf734e1e3ee5a833557894ed7b8f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to multiple compromised WordPress sites hosting PDF files. These links likely serve as a distribution mechanism for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://sunarchegypt.com/userfiles/file/76641250018.pdf In PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7e1558ed5---wetosavuloxusitemun.pdfIn PDF document text
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/79905612491.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/fekuwapojifigafide.pdfIn PDF document text
    • http://okun.su/upload/file/wedenexixepulunugode.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/vituxubi.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/75443477243.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1613998854e98e---pijowo.pdfIn PDF document text
    • http://synagoge-stommeln.de/ckfinder/userfiles/files/rajam.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/kuwaneji.pdfIn PDF document text
    • https://jagamimpi.com/contents/files/23845915169.pdfIn PDF document text
    • http://jyczgj.com/UploadFiles/file///2021091610162330.pdfIn PDF document text
    • https://afmiletisim.afmiletisimajansi.info/resimler/files/82257074807.pdfIn PDF document text
    • http://brilliantsolarpaneling.com/userfiles/file/nevijanafutixoze.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210921_0929AAE499349F4B.pdfIn PDF document text
    • https://www.pessin-location.fr/ckfinder/userfiles/files/23977854060.pdfIn PDF document text
    • http://rtm-plus.com/ckfinder/userfiles/files/makagukuzamowizifigu.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1632396881.pdfIn PDF document text
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614b80840cb28---48521868731.pdfIn PDF document text
    • https://bankubezpieczen.pl/userfiles/file/fozejewaxu.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613ef5099304f---likoxopuresutoxu.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/219ccecde7a2df6a33449158887525bf/66116426694.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=brain+games+mod+apkPDF link annotation
    • http://perfecturology.cafe24.com/upload/editor/imagefile/92541233278.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_off0000b702.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB702 16488 bytes
SHA-256: 21ff090c69117e76618071694d7fdd26901243a83501655e8d8f27c600ee1381
font_01_sfnt_off0000e178.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE178 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f98f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF98F 10736 bytes
SHA-256: 8eb9f6ff43845e49dae9f99e675d1a814e08488f751a1fb25b5d483b3fb5e19b