Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffd70467c223655b…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 22:26:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: efffe514d1b8c561300190e9cf8b7c49 SHA-1: 76e49d59a215858c85ed102da8bde31e30242744 SHA-256: ffd70467c223655b331b6c0ff540572f9a068fd0892d01eee46365565256cc50
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and multiple external links, many of which point to other PDFs hosted on potentially disposable domains. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest a malicious intent to distribute further malware or conduct phishing. The embedded JavaScript, while not fully analyzed due to potential obfuscation, is a common vector for exploiting PDF vulnerabilities or initiating malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.hgekc.com/media/userfiles/file/retexipeja.pdf In PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/37879529603.pdfIn PDF document text
    • https://queensflower.nl/clientfiles/bidipurijexujok.pdfIn PDF document text
    • http://www.dagmarsvendova.cz/admin/js/ckfinder/userfiles/files/jodubovuba.pdfIn PDF document text
    • http://beijingteye.com/upload/files/pojevurakusukukiwatuwid.pdfIn PDF document text
    • https://vico-immobilien.com/ckfinder/userfiles/files/vosureduzedunigutazok.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/nokizusuxukubikuduz.pdfIn PDF document text
    • https://worldmedglobal.com/userfiles/files/3864994022.pdfIn PDF document text
    • https://nghiepvu.udicmanpower.vn/uploads/news_file/47141007166.pdfIn PDF document text
    • http://abpjse.news-read.com/upload/files/29446401336.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/pinoneso.pdfIn PDF document text
    • http://chenruichem.com/upload/files/22985246575.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa38fbd469---zimirikuvas.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210905212506_1u7o5a.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/83901283074.pdfIn PDF document text
    • https://gegeny.hu/uploads/file/wubovifasemi.pdfIn PDF document text
    • http://pk.mo/userfiles/file/dazokufomesiveje.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/deboraw.pdfIn PDF document text
    • https://tvmreza.tv/ckfinder/userfiles/files/volid.pdfIn PDF document text
    • https://planningpvedh.nl/ckfinder/userfiles/files/pijirozuzonudumi.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/zakozifapazoxal.pdfIn PDF document text
    • http://violetstudio.in/userfiles/file/zaseka.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/64355854176.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/82605933930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=naruto+ultimate+ninja+storm+4+road+to+boruto+free+download+androidPDF 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_off0000d767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD767 17604 bytes
SHA-256: 270946cb4fc01b913ad3e5b4661aa834a00e29a4b7079ebb7a59c130de75567a
font_01_sfnt_off0001051d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1051D 11028 bytes
SHA-256: d4b8f9a19a3fda7ecc852efa41e38c61f4d254692f3aa4eb8febbd771829390b
font_02_sfnt_off00011ecb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ECB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1