Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7fd8872b4514586…

MALICIOUS

PDF

74.4 KB Created: 2021-09-25 07:11:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e22ca92abce4bedad2e950f0132be236 SHA-1: cc1ef60418c788c27cb3689cfe8376874711d8e7 SHA-256: b7fd8872b4514586c3bf08b700032d1a483c5dfb521714acc458e9a02a25932d
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 external URIs and link farm patterns, suggesting an attempt to redirect users to malicious sites. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://chcial.ru/uplcv?utm_term=softmaker+office+android+apk PDF link annotation
    • http://xn--lv0az70cxar.tw/uploads/files/202109070209196436.pdfIn PDF document text
    • https://www.osteopathe-montpellier-sud.fr/ckfinder/userfiles/files/suzami.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/mifewigepiruduxesa.pdfIn PDF document text
    • https://podereilmontaleo.it/writable/public/userfiles/file/fajelimudatodoparijed.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147cfdb76ba0---vurudubibezamilevaforirij.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210905195150738.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/pajulamivaxidolixamamu.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/janatepoxipobuzutemuda.pdfIn PDF document text
    • http://pilanatofishing.com/home/sandbox/domains/shelter.sandbox.tritek.hk/public_html/ckfinder/userfiles/files/wejezuwixopovusif.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/napavevolosufovakosep.pdfIn PDF document text
    • http://maidichike.com/upload/files/50940334701.pdfIn PDF document text
    • https://leonardscopysystems.com/home/leonards/public_html/ckfinder/userfiles/files/xejunanitajetu.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/70495359818.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/webomavuxomalomewemazig.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/4101817859.pdfIn PDF document text
    • http://daiichilogistics.com/uploads/news_file/96755816503.pdfIn PDF document text
    • http://urs-certification.com/gais/image/file/zujetovoniwiwedulusav.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131054343f06---27618704317.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/30s7ckkud75h9vp2s3jkkqhf5s/258638748.pdfIn PDF document text
    • https://thediamangroup.com/_images/files/buwiwiluvituzevaze.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_off0000b706.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB706 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF1D 10736 bytes
SHA-256: 9e31d04d9da408d08b0eb45062e1a6675f233ea43b03bf3e70c2f0863204357a
font_02_sfnt_off0000e7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7C6 20812 bytes
SHA-256: 6a025d8feaa1bb4a3e229b274384f671dda73be963672f034b3a2711558b7093