Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8398909b7ec4e54…

MALICIOUS

PDF

81.5 KB Created: 2021-09-17 06:50:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3e96881703bd6df2af1daaded1c77001 SHA-1: b875a9422b571d5c49faa51e4fc97dd3a3f71bd4 SHA-256: f8398909b7ec4e54ff288e18814200a8300bb39c79ff0990cb025c4a5d63a14b
142 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external links, including one pointing to a URL with 'poweramp+crack+apk' in the query string, suggesting a lure for software piracy or malicious downloads. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links on disposable hosting, reinforcing the malicious intent. The ML classifier and ClamAV detection strongly indicate this PDF is malicious, likely serving as a dropper or phishing document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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
  • 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.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://oniceh.ru/uplcv?utm_term=poweramp+crack+apk PDF link annotation
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2d471db24---13286763437.pdfIn PDF document text
    • http://ucg-eg.com/userfiles/file/zazukixixixadig.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/5798896562.pdfIn PDF document text
    • http://gzbaosui.com/uploadfile/files/zoduvujovojemumasoza.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/67302491741.pdfIn PDF document text
    • http://netflor.pl/upload/File/36242659405.pdfIn PDF document text
    • http://onmamtour.com/FileData/ckfinder/files/20210909_CFA6CCCEFB3BD204.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/73128402683.pdfIn PDF document text
    • http://fitviewer.info/files/file/15762661514.pdfIn PDF document text
    • http://tiyuchangdi.com/upload_files/files/20210907_081745.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/d23a52fdb4aac04ad5612d557600855e/88806184021.pdfIn PDF document text
    • https://phm.vn/upload/files/88892695697.pdfIn PDF document text
    • https://congchungnguyenlieu.vnpec.xyz/uploads/files/genilujaxusazelizopi.pdfIn PDF document text
    • https://gym-rectif.fr/ckfinder/userfiles/files/10958154795.pdfIn PDF document text
    • http://ekogamma.pl/javascript/ckfinder/userfiles/files/5963176318.pdfIn PDF document text
    • https://carsen.sk/editor_uploads/system/files/nijinadidug.pdfIn PDF document text
    • http://szkolka-wiercioch.pl/files/file/regotatodotusopame.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/88155691413.pdfIn PDF document text
    • http://goldenpeak.it/userfiles/files/daruxupab.pdfIn PDF document text
    • http://hstechno.com/userData/ebizro_board/file/70193392530.pdfIn PDF document text
    • https://xn--b8qxb801j.tw/upload/files/gokovilorawiwukufulul.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/newegamixukizu.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_off0000d815.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD815 10208 bytes
SHA-256: c28f0d8e03ee684c5d6e10bd9181a7940771c1729196476b8e25d706e3849984
font_01_sfnt_off0000ef16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10728 19012 bytes
SHA-256: 503e6000621dfd0d53fa0b69e4225365a462097032581606997d1ad3782d462a