Malicious PDF — malware analysis report

Static analysis result for SHA-256 f55dde9b79160c32…

MALICIOUS

PDF

85.0 KB Created: 2021-06-28 06:57:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0828ee3112655daf1d3c56e1c7c19a70 SHA-1: acf6569b2cf733bdb67817c9c8cfe46b5766b57b SHA-256: f55dde9b79160c32a6ddd5abd74375d0bdaff86080ea79e7b3fa905341c90b3a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting. The heuristic firings indicate it functions as a link farm, likely intended to lure users to phishing pages or download further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://chcial.ru/uplcv?utm_term=round+flaky+patches+on+skin
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/b410bca78ce18e449daee264e265d297/jibewenadutavozoroma.pdf
    • https://xaydungdonggia.com/app/webroot/files/images/pages/files/gobomazofatap.pdf
    • https://alakharia.com/public_html/userfiles/file/46837154810.pdf
    • http://thietbiotoviet.com/Images_upload/files/vapepudojomapanuluvi.pdf
    • http://pogotowienaukowe.com/Upload/file/jorafujudivazudubilux.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a09304018f0---5852120266.pdf
    • https://mollis.rs//files/82983148333.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/8bd4804ece49ebb457062195f71a7cd0/85155337602.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d3f7f136416967ed6201f3a6e6d4c7ba/43086804581.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5897bcf373---dibafawufopixorafilagos.pdf
    • https://fnb-concepts.com/images/uploads/files/49864603508.pdf
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/526962650.pdf
    • http://mp-hd.de/data/aktualnosci_imgs/file/92960211268.pdf
    • https://pmms-online.com/assets/file/xesulegebonaku.pdf
    • http://amphorabeautyclub.com/campannas/file/jabiragigapofakesiluta.pdf
    • https://matrainagycsalados.hu/userfiles/file/putegib.pdf
    • http://fitnessklub-impuls.pl/uploads/assets/file/40179951129.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c79860923c9---45553710512.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083fb9aaf204---56193262431.pdf
    • http://keramann.ru/uploads/files/37516872566.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb0a5ab1bd---73973362018.pdf
    • https://lasvegasrebath.com/wp-content/plugins/super-forms/uploads/php/files/2d9c6d400abd8c4a80a6ef79e30c54b7/57408715967.pdf
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/ojb7r3im9brv1i3unu90s3mlla/gefijakanenitaro.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7ef.bin
0292ef8e321dc0b7bfe86ff7f726d721f1f28ef5baecc87afcc5c5f36d0aef26
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EF 10968 bytes
font_01_sfnt_off00010171.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10171 16792 bytes
font_02_sfnt_off00011983.bin
8d5d0db0776e2dfab1ea6684132119690183b67250fcd7e7d88ca6ed26a9b021
pdf-font-stream PDF embedded font (sfnt) at offset 0x11983 16968 bytes