Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc9e0b5395209582…

MALICIOUS

PDF

77.5 KB Created: 2021-09-04 16:04:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7f223c19b511e6884ee8173d9f53b0fb SHA-1: 5e117cd33a45bbc9540e9829da57ea14ad8923d3 SHA-256: bc9e0b53952095823d99ca53513770225ede05990b59a571138d3ee7496de9f5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and a significant number of external links, many of which point to compromised WordPress sites or disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 7

  • 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.
  • 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 http://thuduchouse.vn/pics/file/5762678958.pdf In PDF document text
    • http://criollo-cocoa.com/userfiles/file/18101402681.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160f7e3790f2c2---numitosatafusaneb.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/b9df8d271b04919e94cfed5aae533d59/bufovewakuputisigopap.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160771ca1db5ae---vesetujovivavon.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161266744ef1d2---34163355416.pdfIn PDF document text
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe45d9c09e---610526403.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/4f85d1b3f1407eae9624e3036d8bb8d1/noradalawu.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/76493313724.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161093adb352d0---93576322695.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/5d1dc1117d07cc2cb335039103ef0d48/tunazenugetafit.pdfIn PDF document text
    • http://foto-video.ch/userfiles/files/pedenixi.pdfIn PDF document text
    • https://melz-feu.ru/upload/13540393922.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/i5l4hsmdb7aoiadll33otcb05l/nupokepofasabenerali.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/9297029125.pdfIn PDF document text
    • http://starsunited.at/upload/files/35012474758.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/95309261738.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/cdetdqsjgcn220bf5f6enav5s1/noparawulonaxuwuf.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160b171d91e8a9---filajaxux.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160f28cd349676---dukalurilizinexakebiz.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/zugegifozukegexal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=functions+of+international+court+of+justice+pdfPDF link annotation
    • 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_off0000cc7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC7F 16692 bytes
SHA-256: bf4a92904780e958b0e86b5d1045c16ac1f1d5d7d87c0d46b211c2a88357a3e5
font_01_sfnt_off0000f758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF758 10820 bytes
SHA-256: 4f63b70d5fd97557c67782e87762fea1d4a36c9561a1a2a8ddd435baae3e1c4b
font_02_sfnt_off00011064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11064 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1