Malicious PDF — malware analysis report

Static analysis result for SHA-256 de25fa5dcbff85a1…

MALICIOUS

PDF

71.8 KB Created: 2021-09-11 17:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: abfbae7587c1e9c6800e5c09c7a2f6d4 SHA-1: d8481243a52a54639858eb70da3fc056759b34b9 SHA-256: de25fa5dcbff85a1fe779e8b6b335223868d2aaf9e9b3363747e268c8ba550bf
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Numerous heuristics indicate it functions as a link farm, distributing links across many distinct, often disposable, domains. The embedded URLs, such as 'https://smidgel.ru/uplcv?utm_term=games+like+animal+crossing+on+android', likely lead to phishing pages or further malware downloads, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • 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://smidgel.ru/uplcv?utm_term=games+like+animal+crossing+on+android PDF link annotation
    • http://massimosusto.eu/userfiles/files/23798444450.pdfIn PDF document text
    • http://vervesimuhub.com/userfiles/file/82910892365.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/pozowo.pdfIn PDF document text
    • http://dreamcatcherltd.com/userfiles/file/sebopedeb.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161344041a8849---ziposagalimofomagoze.pdfIn PDF document text
    • http://showpelec.com/data/file/20210909_112237_355.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/4500173402.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/41vqa6n08lq6vltj7kjoego1ie/zupozemisekuz.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613799c0a1cd6---1308240551.pdfIn PDF document text
    • https://self-storage.sg/images/uploadedimages/file/wixujagebagegubekad.pdfIn PDF document text
    • https://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/32097609931.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/tatuxudirolaxefokewedi.pdfIn PDF document text
    • http://syuncyoku.jp/upload/file/nunivotifitowafa.pdfIn PDF document text
    • http://salon-urody-bellis.pl/images/file/tobet.pdfIn PDF document text
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/tokin.pdfIn PDF document text
    • https://mobile-translator.eu/app/webroot/media/files/tigedutili.pdfIn PDF document text
    • http://kennycojewelry.com/userfiles/files/202109/1630851547.pdfIn PDF document text
    • http://vyveva.eu/UserFiles/File/fupuvipojixorafetuje.pdfIn PDF document text
    • http://euro-ex.com/images/blog/file/68432515446.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/resumikimetetizuvako.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/xekobomabojafida.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/65809339034.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/16303074545.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_off0000b92e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB92E 10748 bytes
SHA-256: 7525b3ec8135e1eced796d3bfbee9561197acce4fb21ea968e35f85ff153b114
font_01_sfnt_off0000d19d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD19D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e9af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AF 15704 bytes
SHA-256: 4be7574d76c9d43706637a9b991dda2b5fb424b77db5d72e95cb3f721de055c3