Malicious PDF — malware analysis report

Static analysis result for SHA-256 cfb2e2451d67090f…

MALICIOUS

PDF

87.5 KB Created: 2021-09-23 03:22:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 852d569553d0701bd5f1425819a81a3c SHA-1: 82ef316e507dce56a1c13c414a1b0277adeb3409 SHA-256: cfb2e2451d67090f1a6ab4598d8f92014b0ba3e066211e6253e39dd5e03e90af
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggest the document is designed to redirect users to potentially harmful websites. While no scripts were explicitly extracted, the nature of the PDF and its embedded links strongly suggest it's part of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nomylo.ru/uplcv?utm_term=find+the+value+of+x+fractions PDF link annotation
    • https://commonwealthsportsawards.com/userfiles/file/77209705521.pdfIn PDF document text
    • https://poganyvolgyi.hu/userfiles/file/96503411668.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210908030812.pdfIn PDF document text
    • http://chatyzvule.cz/uploads/82700967215.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/rolaju.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/6046753774.pdfIn PDF document text
    • http://canadianartistic.com/userfiles/file/govamimiforuso.pdfIn PDF document text
    • http://gardena.crazyrockinsushi.com/uploads/files/pelivubowopolami.pdfIn PDF document text
    • http://nenayu.com/filespath/files/20210910023026.pdfIn PDF document text
    • https://tigapilar.com/upload/files/55255701069.pdfIn PDF document text
    • https://pastravariaizvoarelebratiei.ro/images/file/66030960451.pdfIn PDF document text
    • https://adtw1.com/ckfinder/userfiles/files/xaxuvagikaxajokiwometiw.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/46431085942.pdfIn PDF document text
    • http://worldcar.jp/userfiles/files/zelegotizavobim.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/69524816411.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/92020631612.pdfIn PDF document text
    • https://jnvhardoi.org/ckfinder/userfiles/files/tulelefoxavi.pdfIn PDF document text
    • http://mansiya.com/uploadfile/files/pixuxejexewixalolad.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/43163823592.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/vizuvezeluwaf.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/tusebok.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/161431a315b03e---masuzigudedazow.pdfIn PDF document text
    • https://ijp2.com/contents/files/86641237818.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16131251b4e53e---90199800757.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pagelago.pdfIn PDF document text
    • http://hkalc.com/userfiles/fixebenatogigoj.pdfIn PDF document text
    • http://stmrcstvm.com/userfiles/file/takivasixebosof.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_off0000ecd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD9 10816 bytes
SHA-256: b8104f92e476a7d8a2c50a3c9a0f1f291c3b59a1bc4a946b4df7a0be7552574e
font_01_sfnt_off000105bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011dcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCF 19148 bytes
SHA-256: 95143031a5561e8c7c62422ad7d83a330c2f67441a01137fbf7f214a64151eeb