Malicious PDF — malware analysis report

Static analysis result for SHA-256 16f7b70559c935d8…

MALICIOUS

PDF

80.9 KB Created: 2021-09-16 13:03:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c80c1d6c795f521137b54a500f0ab23d SHA-1: 79ca57bf2e06f86632fd8698bc5c6d475187e3f3 SHA-256: 16f7b70559c935d8c883678c67002f3d17f08ac31295860b403ee07d4ccf8a86
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, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads, suggesting it's used to distribute further malicious content. Although no scripts were explicitly extracted, the PDF structure and link farm nature imply an attempt to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc70a60699---jipetemajeguze.pdf In PDF document text
    • https://bhopalliteraturefestival.com/mpsdp/uploads/files/tekemizupuxep.pdfIn PDF document text
    • http://melvin.cz/data/10428075482.pdfIn PDF document text
    • https://cyklo-wellness-penzion-palice.cz/content/16782642985.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/nelotekagazexavex.pdfIn PDF document text
    • http://inphilong.com/upload/files/fijifizekapedabugisaze.pdfIn PDF document text
    • http://seidels-mineralienwelt.de/images/uploaded/file/nigorulitukuzasowiketi.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210908011047.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/c97c461f22c5cc1b1967400fe52efcd3/12781627318.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/xuramorabezumunot.pdfIn PDF document text
    • http://baozhaopharma.com/upload/files/99501584938.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/baturoxawekibet.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/sazazesed.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/18547827583.pdfIn PDF document text
    • http://holmeslawfirm-iowa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/70885209609.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/89198848662.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/depidara.pdfIn PDF document text
    • https://connatlas.com/home/conn/public_html/ckfinder/userfiles/files/wudobikuxokewuwezabe.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/lamuzolafakulidide.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/69355946889.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/hi3aff4khbu94kpb6ng266knq3/15199102874.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329afc50a65---femobigowuduve.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/32888910821.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=download+minecraft+pocket+edition+versi+baru+2020PDF link annotation
    • 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_off0000d59a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59A 11508 bytes
SHA-256: 80412a2a902fee8aa0a124d97f403277917f14dea342047884bd1c7babc83e66
font_01_sfnt_off0000f0a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A9 17408 bytes
SHA-256: 5760c5776ac823e6fb576494907c565c898c7c2f5ca6d63f2896a9978b18ee48
font_02_sfnt_off00011e06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1