Malicious PDF — malware analysis report

Static analysis result for SHA-256 f73b774ce25154b8…

MALICIOUS

PDF

74.1 KB Created: 2021-09-24 19:46:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 583cbc0385e87b8c2ea7a12351af48c0 SHA-1: d2ff6a44091d2c2a27747ec55f4ad620c275943b SHA-256: f73b774ce25154b8c310d0bd00f3f896dd3fb13c071cfdbbabc072f2bad850ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to potentially malicious content, indicated by heuristics flagging it as a link farm on disposable hosting and compromised CMS uploads. ClamAV detection and ML classification confirm its malicious nature, identifying it as a phishing trojan. The presence of external URIs suggests an attempt to lure users to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://cructi.ru/uplcv?utm_term=computer+networking+7th+edition+pdf PDF link annotation
    • https://nedimgame.net/calisma2/files/uploads/10399130985.pdfIn PDF document text
    • https://nieruchomoscikomercyjne.co/files/file/lopoxerobezeximebomudo.pdfIn PDF document text
    • https://editions-tlp.fr/ckfinder/userfiles/files/58603671246.pdfIn PDF document text
    • http://vina2002.com/uploads/files/99539607761.pdfIn PDF document text
    • http://pradakshinam.com/fck_uploads/file/52736837666.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/vifezanadogugube.pdfIn PDF document text
    • http://life-homeshop.com/asset/uploads/files/28579651683.pdfIn PDF document text
    • http://bdn10.cz/files/file/liwuwumatasupidiga.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/berubakilavipu.pdfIn PDF document text
    • http://tucholainfo.pl/userfiles/file/87934985426.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/161408f5b00be1---zonitikirorenabaxoveg.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109201950405512.pdfIn PDF document text
    • http://suspensionestg.mx/userfiles/file/65884783334.pdfIn PDF document text
    • http://digifast.cz/userfiles/laxonuporifetazibumirujo.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/54282471562.pdfIn PDF document text
    • https://bgg.pirkitpadangas.lt/ckfinder/userfiles/files/61920522049.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/zevudefutali.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/211276f0905210ea7b8a605e38ac63eb/68203327988.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/63409302028.pdfIn PDF document text
    • https://lexcyberia.com/userfiles/files/42942175679.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a9a099f9c---pomavisolazubekujepigov.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/41409890156.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/bomepofoxapofivikitafon.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/3157b75a1b84cb2616e6138e8e0416fc/74253812715.pdfIn PDF document text
    • http://rinsacars.com/files/others/janitoxibesap.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_off0000b8f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8F1 10928 bytes
SHA-256: 724a5262c52bb1911944bf1b1e2739cf1d8c4df0926afbd5fd7525d6574d9d4b
font_01_sfnt_off0000d1fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0D 18776 bytes
SHA-256: 1226c6f489b340478c16ca4b522df220b62a7b1b0e469492c713d08cc65007cb