Malicious PDF — malware analysis report

Static analysis result for SHA-256 f77eb0cd2fd18c68…

MALICIOUS

PDF

78.7 KB Created: 2021-09-18 10:18:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 24367df6133975e4fe819dd97b030f0d SHA-1: 8d3620dd6b6c4f09534c861342b1658d1983ff45 SHA-256: f77eb0cd2fd18c6870aad6ea4f288c44563d191850229818d282eaab76f2571a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of link farms hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution via redirection. The embedded JavaScript (T1059.007) is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=gta+sa+v1+08+cleo+mod+apk PDF link annotation
    • http://diegogenna.it/userfiles/files/58924645034.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/xosenasudi.pdfIn PDF document text
    • http://jngf.cn/files/file/21794934245.pdfIn PDF document text
    • http://manu-transport.com/documents/file/vodejonasukovemotosefo.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/bexifuxanafolabafifejagim.pdfIn PDF document text
    • https://shian-jin.com/UserFiles/files/30110901626.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/93735827842.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138ad7d65da9---50464511807.pdfIn PDF document text
    • http://balbu.hu/uploads/news/file/44542210097.pdfIn PDF document text
    • https://alcoolassistance-creuse.net/www/site/js/ckfinder/userfiles/files/80724137453.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/87723492928.pdfIn PDF document text
    • http://directopinion.biz/uploads/FCK_files/file/kesux.pdfIn PDF document text
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/96563544500.pdfIn PDF document text
    • http://vino-charlie.cz/userfiles/file/zojarabinifiguforizomeb.pdfIn PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/sugujosesotujaw.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613793ebe4d59---jugeto.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/0prk12pkbk3o6j50v4o0lciotf/vugamotewiziga.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/kizofunuxuzarisanamibe.pdfIn PDF document text
    • https://sofupingame.net/calisma2/files/uploads/vabadagijazetojomu.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210916115706.pdfIn PDF document text
    • http://schokofontaenen.de/idata/tekonagobulemisefaku.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613396eee9c07---9831646800.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/4jegnjbkr5ghlis2unnqc7vf5g/sebigasitaramil.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_off0000cd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD53 17820 bytes
SHA-256: 755de854c5917b613b56e8ab5ff3bcf1669317d88ad93d82957885a3a09985c4
font_01_sfnt_off0000fb3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011356.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11356 10960 bytes
SHA-256: b729268e829f4d8b7f9aa06460b48c1ba14e2f99f1d90a0037df1c475438f8b7