Malicious PDF — malware analysis report

Static analysis result for SHA-256 c793b3a3ab3e8a90…

MALICIOUS

PDF

69.5 KB Created: 2021-09-24 23:04:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e1177f71e98cce5f7105a16deef95c59 SHA-1: 45e81805fe978607a4736568104703a7d40810ad SHA-256: c793b3a3ab3e8a907ff1bc3ff98d61841db8eb31d3af65b2bb85d8dc2f6cb3e3
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially malicious PDF files hosted on various websites. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a technique to obscure the true malicious destination by using a large number of links on disposable hosting. While no scripts were directly extracted, the ML classifier strongly suggests malicious intent, likely involving the exploitation of PDF vulnerabilities or social engineering to trick users into downloading further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 4

  • 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://paroles-vives.com/ckfinder/userfiles/files/10061350719.pdf In PDF document text
    • http://mosvag.ru/img/lib/file/xuxukalafebimegifatano.pdfIn PDF document text
    • http://vishwkarmaenterprises.com/webroot/img/userfiles/files/23127097882.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/85419377038.pdfIn PDF document text
    • https://reparation-mobile.net/userfiles/file/71697465632.pdfIn PDF document text
    • http://wingmanresearch.com/userfiles/files/17234756578.pdfIn PDF document text
    • http://jowinbio.com/upload/files/202109120518155217.pdfIn PDF document text
    • http://dunakeszi.varosom.hu/userfiles/files/bipilikol.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/f6248d7883125a22fdfe38015398c4b4/48432881508.pdfIn PDF document text
    • http://mitcostruttori.it/userfiles/files/bixowufifadikiw.pdfIn PDF document text
    • https://asiapharma.la/files/files/26455482263.pdfIn PDF document text
    • http://e-menu.hu/editor_up/wuvajesuwivip.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/49517263999.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/53561138734.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/wekamefupipemoxave.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/69885055718.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/somabinig.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/tufuvuredepawiz.pdfIn PDF document text
    • http://cdjuchuan.com/upload/files/94017931882.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/78538162432.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/79993890703.pdfIn PDF document text
    • https://tiguan-wiki.ru/file/57106638339.pdfIn PDF document text
    • https://termofriz.rs/files/23578835758.pdfIn PDF document text
    • https://sinarwaja.com/account/files/zuwekamiposijejajiduwe.pdfIn PDF document text
    • https://samsungklima.net/upload/ckfinder/files/tupelokejimuroragusomuves.pdfIn PDF document text
    • http://finemetal-cn.com/upload/files/88990699831.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=hydropower+flow+chartPDF 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_off0000b01a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB01A 10544 bytes
SHA-256: 01c3c4fa461b25413894e6d1a483777d7f3bd91bac4af9cec624245e7916f9fd
font_01_sfnt_off0000c848.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC848 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e05a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05A 15756 bytes
SHA-256: 9f55fddd0b3937998cdc1c0708e2a7ab166506eefdf987a211ecaf1fcd092727