Malicious PDF — malware analysis report

Static analysis result for SHA-256 22547e85d14aa1ec…

MALICIOUS

PDF

71.1 KB Created: 2021-09-18 22:45:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5bdd092d0860c2c47901b13c010628df SHA-1: add2d5f72fd700c7ca8d78dc36a3e59baae9ef49 SHA-256: 22547e85d14aa1ecbba4eb3057bbfc45ec8c6054bb90177cde63c262e62b853c
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many of which are algorithmically generated and hosted on disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards it being used to redirect users to malicious sites, likely as part of a phishing campaign or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://garglob.ru/uplcv?utm_term=kindle+paperwhite+instructions PDF link annotation
    • http://www.tivafa.hu/upload/file/girepixewazekulebusava.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/72856154894.pdfIn PDF document text
    • https://almuhja.com/ckfinder/userfiles/files/zemizawebajotulit.pdfIn PDF document text
    • https://kalashad.com/userfiles/file/xatem.pdfIn PDF document text
    • https://vnnc.vn/img-hdmedia/files/siwapevelupog.pdfIn PDF document text
    • http://masan315.net/board/imagefile/file/85313116055.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/nagigojozumu.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16141cca517cbd---rolenadaz.pdfIn PDF document text
    • http://www.fonfe.com/uploads/files/kunimixo.pdfIn PDF document text
    • http://arsvet.ru/img/upload/pularonugetenep.pdfIn PDF document text
    • http://clinicaveterinariacittadivignola.com/userfiles/files/gukavodewutinujevudugumab.pdfIn PDF document text
    • http://antonioruizabogados.es/userfiles/file/lutaxi.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/dujaxotebotobobupir.pdfIn PDF document text
    • http://ganteltechnology.com/system/userfiles/file/96445027966.pdfIn PDF document text
    • http://vetranhtuong.info/luutru/files/48001728705.pdfIn PDF document text
    • http://agedwedfjtj.pretty-match.com/upload/files/nozavoridizanumiwusuji.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gerapuke.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-18/20210918113347615942.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/dofusewujekiramefotavixe.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/89421959885.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/64578643598.pdfIn PDF document text
    • http://rfaaa.com/UploadFile/file/20210903201812134.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_off0000b4a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4A2 10788 bytes
SHA-256: 65648b59b6b1899883f36949cc7c59331a9b7d7a74b3461ae54598c7320e7ff9
font_01_sfnt_off0000cd75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD75 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e587.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE587 16280 bytes
SHA-256: e5406387addb97fea590672e4c45e6d5c4f6b7595320bb207a42daea5f7941e5