Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa0557b0318930e8…

MALICIOUS

PDF

76.8 KB Created: 2021-09-15 21:00:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e0d6fa7614f1de1cde80be1d93a7cf77 SHA-1: decb4bd32eb85f3f35eb5eabb62ca19e212638aa SHA-256: fa0557b0318930e8319b28809f0ee03ec1a44c039c0ee96bbafa29d9ee185ee9
174 Risk Score

Malware Insights

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

The sample is a PDF file containing embedded JavaScript and multiple external links, many of which point to disposable hosting. The heuristic 'PDF_RANDOM_URL_LINK' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a strong likelihood of this document being used as part of a phishing or malware distribution campaign. The embedded JavaScript, while not fully analyzed, likely contributes to the malicious functionality, possibly by redirecting the user or initiating a download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 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 https://queure.ru/uplcv?utm_term=metodo+de+arandelas+pdf PDF link annotation
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c6e227086---14938060657.pdfIn PDF document text
    • http://ambulatorioveterinarioscapindandrea.it/userfiles/files/72134276934.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/pobijipugaketo.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/lomukoxojalifotilojijulob.pdfIn PDF document text
    • http://moretonassets.net/userfiles/nuregule.pdfIn PDF document text
    • https://kar360.com/resimler/files/suzozorig.pdfIn PDF document text
    • https://corumosmanlimakina.com/js/ckfinder/userfiles/files/20362679324.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/16932151723.pdfIn PDF document text
    • https://ppntassone.it/dati/upload/file/xanunopabutewijemuxi.pdfIn PDF document text
    • https://gym-rectif.fr/ckfinder/userfiles/files/zaxapogojifufuxupegid.pdfIn PDF document text
    • http://df-2.de/images/daten/file/36551606746.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/78627635994.pdfIn PDF document text
    • https://adikkedua.com/contents/files/66414055526.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/2120513214.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/nijobefabugulebebobarodi.pdfIn PDF document text
    • http://www.agot.pl/upload/file/39204962959.pdfIn PDF document text
    • http://timnhanhonline.com/upload/files/vibekufe.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/walej.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/51883700046.pdfIn PDF document text
    • http://gvs-russia.ru/admin/ckfinder/userfiles/files/3572563330.pdfIn PDF document text
    • https://mp2020.csysadmin.com/ckfinder/userfiles/files/35051928062.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/vumeke.pdfIn PDF document text
    • http://dainindo.com/Uploads/userfiles/files/koruzavutubum.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_off0000c3ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3AC 10392 bytes
SHA-256: 052cc1aa9472eb0ca6e647d3e65ead2546cb8006a15b83dff2981463373bae55
font_01_sfnt_off0000db51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB51 19512 bytes
SHA-256: 111e5b074683258e12e37b971bc206f0a5a1a1f1be39bcf65b3f120dcc842131
font_02_sfnt_off00010d7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1