Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfbe34e2d804fdd4…

MALICIOUS

PDF

80.9 KB Created: 2021-09-15 09:49:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 170777d1cad203f7a3ceb2318dcb15f7 SHA-1: 93736b3674dbc63e41f7489dff5242fb938ef917 SHA-256: cfbe34e2d804fdd44a8fdb1f2f87b471feadfb6b088aceb765f642fe8f84e7a2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of embedded URLs and the overall structure strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://nomylo.ru/uplcv?utm_term=android+ios+multiplayer+games PDF link annotation
    • http://www.elstar.ru/uploads/files/25961284587.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/saxisetepibogubub.pdfIn PDF document text
    • http://annabarons.com/files/files/97261826955.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/161416e560d70e---nanemefewalok.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/6a775af10246b3834271379cddf9b923/9862963879.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/35955181735.pdfIn PDF document text
    • http://orkoien.com/userfiles/files/zewetamadisivawenobur.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613569a79091d---muloj.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/neribeginojuderulor.pdfIn PDF document text
    • http://zeroseistudio.eu/userfiles/files/42179331299.pdfIn PDF document text
    • http://takramaipai.com/mypicture/file/83604019541.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/kevoxagage.pdfIn PDF document text
    • https://lidiyageorgieva.com/ckfinder/userfiles/files/80046706044.pdfIn PDF document text
    • https://butchercurnow.com/img/shop/contents/91049883377.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/vatutat.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/20221885565.pdfIn PDF document text
    • http://tamtamphat.com/upload/files/4490757748.pdfIn PDF document text
    • http://smm-mm.com/uploads/news_file/lugog.pdfIn PDF document text
    • https://baigiangtoanhoc.com/upload/files/dokusow.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/92788910977.pdfIn PDF document text
    • https://pasarangroup1.com/contents/files/77275603569.pdfIn PDF document text
    • http://lepetitjaunais.com/userfiles/file/15701701396.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/3562355207.pdfIn PDF document text
    • http://aktasmatbaacilik.com/resimlerfiles/wetixovodepukizadekozupel.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_off0000d7d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7D2 17468 bytes
SHA-256: 6de8f19b778c92c392d86e97d8f429011e6ba90c3cadf3ca5dfa11d60a364615
font_01_sfnt_off00010489.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10489 10932 bytes
SHA-256: 081547688e21851f98a2e147dd23cdec734992227bbdf92e951c0b989f10e52b
font_02_sfnt_off00011db2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1