Malicious PDF — malware analysis report

Static analysis result for SHA-256 126e9e91979b2e57…

MALICIOUS

PDF

79.9 KB Created: 2021-09-17 11:22:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 17e86de4b4df76b1783d9cb0cd25a943 SHA-1: bb4f61469d45d0bd2aa798362ee70a5cc3af7f94 SHA-256: 126e9e91979b2e57f57b96bf39f35e5e06e62f5d9aa982f82da858c453dd42fb
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or delivering malicious content. The presence of numerous external URLs, many of which appear to be link farms on disposable hosting, suggests a phishing or credential harvesting attempt. ClamAV detection and ML classification strongly indicate malicious intent, likely involving the download and execution of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://medvor.ru/uplcv?utm_term=video+volume+booster+apk PDF link annotation
    • http://www.egymast-segito.hu/uploaded/fck/file/95088173624.pdfIn PDF document text
    • https://mhreng.com/userfiles/file/57908764590.pdfIn PDF document text
    • http://saipanbooking.com/FileData/ckfinder/files/20210916_A6D0ED4EBE796C54.pdfIn PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/72404856779.pdfIn PDF document text
    • http://cetis156.neutronds.com/assets/js/ckfinder/userfiles/files/wodazenalavapuvadaliwapa.pdfIn PDF document text
    • https://svltv.in/userfiles/files/84605388050.pdfIn PDF document text
    • http://ccsctda.com/ckfinder/userfiles/files/20210914_101407.pdfIn PDF document text
    • http://epicridesnepal.com/files/nogimajokalowu.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/giremexogujo.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161394c7ba4cd3---55604051511.pdfIn PDF document text
    • https://delphin-restaurant.com/ckfinder/upload/files/39753221467.pdfIn PDF document text
    • http://tetobox-budapest.hu/uploads/files/sosoxebofubuzeguwasefu.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/zetubajuwesetepovek.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/zufiwus.pdfIn PDF document text
    • http://budropol.de/Upload/file/71291336686.pdfIn PDF document text
    • https://ltes2.tw-goods.com/UserFiles/files/63330881788.pdfIn PDF document text
    • http://atanasijornet.net/uploads/ckfinder/files/65409954448.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/97135979481.pdfIn PDF document text
    • https://protum.se/file/38892525581.pdfIn PDF document text
    • http://www.santamyoga.be/images/file/84964114659.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/tinuw.pdfIn PDF document text
    • https://5a.ro/ckfinder/userfiles/files/61181701075.pdfIn PDF document text
    • http://bilafafafa.com/shopadmin/upload/files/4255767042.pdfIn PDF document text
    • https://ihotel2b.com/upfiles/editor/files/tudetimukokam.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/libub.pdfIn PDF document text
    • http://jjburgerut.com/uploads/files/31221300887.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_off0000d1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C2 10816 bytes
SHA-256: 5c17749d5263fe751cff1096df03f00e2055003db28d2116ec35b4edcc68f3e1
font_01_sfnt_off0000ea88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001029a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1029A 18096 bytes
SHA-256: afbc6b6767d88a1f358549bea62b02690db79daf2a4d06730bb8a8284a5249fd