Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a5bba1ab9c8d60f…

MALICIOUS

PDF

80.0 KB Created: 2021-09-08 22:22:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: e1b40ae59ccf9b790e0233b5d8781125 SHA-1: 99b6365ef73583962d977c97749a0eaae65ea4c1 SHA-256: 9a5bba1ab9c8d60f08064737993d196f77773cd7ce3955ac36fd2639b85e6512
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of links, many pointing to compromised WordPress sites or disposable domains, characteristic of a link farm used to distribute malicious content or phish for credentials. The document body is heavily obfuscated and appears to be junk data, suggesting the primary function is to host these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://xn--p3t29jo1ed4o4xw.tw/upload/files/55364351281.pdf In PDF document text
    • https://12tiga.com/contents/files/70656434079.pdfIn PDF document text
    • https://adikketiga.com/contents/files/dafukisojutewasigidawe.pdfIn PDF document text
    • https://buyafranchise.org/files/files/morumewewobezizanilo.pdfIn PDF document text
    • http://alotercuman.com/ckfinder/userfiles/files/60193421746.pdfIn PDF document text
    • http://www.nbc.com.vn/ckfinder/userfiles/files/42659274238.pdfIn PDF document text
    • http://zhhyhb.com/uploadfiles/files/pixidapitigikezid.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/90399439360.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0a21949f8---41763482875.pdfIn PDF document text
    • https://rajaunited.com/contents/files/mufirosakemaxir.pdfIn PDF document text
    • http://stauarchitetti.eu/userfiles/files/gunogoposetuxubor.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/7adb352f986a73334adc6fbed7ee8ad6/7468969276.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613483320d7a3---12652739841.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16130da7c65218---50068884214.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/nexek.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/xitawodurefasulawokofov.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/vowifitomedovinezeniji.pdfIn PDF document text
    • http://babamoleskine.com/files/file/dikigesebox.pdfIn PDF document text
    • http://firegallery.ru/img/upload/vizikupoxolivomifeke.pdfIn PDF document text
    • https://webmenuplus.com/images/file/65176660595.pdfIn PDF document text
    • https://www.jancsoalapitvany.hu/ckfinder/userfiles/files/45145082871.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=cara+menggunakan+gta+img+tool+androidPDF 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_off0000d4bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4BC 10648 bytes
SHA-256: 659c1255da328594a9e1a83c1d7756389c317d5852dee582db2873b663c906d3
font_01_sfnt_off0000ecd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD8 17484 bytes
SHA-256: 0208ad9f560150d98f2aa79fc570fcdeca0a135fd61270e0d021d10036abf387
font_02_sfnt_off00011a81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1