Malicious PDF — malware analysis report

Static analysis result for SHA-256 578b405fefbb8058…

MALICIOUS

PDF

88.0 KB Created: 2021-09-19 02:14:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7b9e5214efe6ac2ddf07d548c4991f4a SHA-1: 8e00ac4d4df2eed6877cdf55f3c6310ae07c6e28 SHA-256: 578b405fefbb8058bee18167f357cda73075ec5bcd362f25904a20d82de8ae2a
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with a high-confidence heuristic identifying it as a link farm on disposable hosting. One specific link, http://ambulatorioveterinariosantanna.eu/userfiles/files/15134983504.pdf, was flagged as a random URL. The ML classifier and ClamAV detection strongly indicate maliciousness, likely for phishing or malware delivery via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • 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.
  • 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://dalton-english.com/userfiles/file/pagemoj.pdf In PDF document text
    • https://mehreganimaging.com/images/upload/files/xoxesisivew.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/woxuwazufum.pdfIn PDF document text
    • http://ambulatorioveterinariosantanna.eu/userfiles/files/15134983504.pdfIn PDF document text
    • http://sporteambiente.it/ckfinder/userfiles/files/33804875039.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/nonugebasafimoges.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/volikularoperubunev.pdfIn PDF document text
    • http://snp-ent.com/files/fckeditor/file/7655048536143c50a21c63.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/2021917912294149.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/dc8be79bafceda19f814c347818e9bc5/75381442205.pdfIn PDF document text
    • http://pferdplus.at/sites/pferdplus.at/files/file/41957380143.pdfIn PDF document text
    • http://goksirkrupskimlyn.pl/img/upload/files/zejaxewizowebematokov.pdfIn PDF document text
    • http://tasteofruraleurope.eu/upload/File/78312303130.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/ba9887d7f22082f33a121d89916d8952/sivafat.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/94438228119.pdfIn PDF document text
    • http://w-w.cn/isee/pfm/cms/uploadfile/fck/file/69240787126.pdfIn PDF document text
    • http://kunmobile.vn/files/uploaded/20210909/file/busovazilo.pdfIn PDF document text
    • http://tokyoto.pl/UserFiles/file/57801069787.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/wanelutolatelozosa.pdfIn PDF document text
    • http://laptopcuhaiphong.vn/upload/files/9367819696.pdfIn PDF document text
    • http://www.polni.si/Images/files/virefetuwetegutunurubuj.pdfIn PDF document text
    • http://codienlanhminhquang.com/upload/files/tugoxigimigemanotaxulude.pdfIn PDF document text
    • http://thepducphat.com/upload/files/lugitor.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/gigetonozuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=the+throne+of+fire+graphic+novel+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_off0000f352.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF352 18052 bytes
SHA-256: 1379d24e72ebef5ecae8985a25b74ed9a4794357b1817ebd1f3cc2764a54525c
font_01_sfnt_off0001221f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1221F 10760 bytes
SHA-256: 5ef902b9e61ec3899db1bba677bdc97e7bd17b72b8552db3606eb973792126b4
font_02_sfnt_off00013aa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1