Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b946cd92d953ee…

MALICIOUS

PDF

73.4 KB Created: 2021-06-24 14:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 84bdd2aada26a2834f36b6a731ff007e SHA-1: c9a694bdea40aeb1a88c757183abf87c0978ea8c SHA-256: a1b946cd92d953ee9f1f19c733d9300197de89168a67221e39fdadf635931d2c
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ketchas.ru/uplcv?utm_term=update+to+android+9+apk PDF link annotation
    • http://kalikraft.com/images/file/kazamosoturuwop.pdfIn PDF document text
    • https://heider.ru/wp-content/plugins/super-forms/uploads/php/files/6840683b468c0cf159333a79ee212015/walulubomamixafozubo.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/fefezizedorujejuk.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/r5gbf2tcl3ct4qkt5q93frna6n/77757716822.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/sudajitubovupaw.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0dd8c931f6---5242139330.pdfIn PDF document text
    • http://k1a.ru/images/files/file/jotisuwijakeponibu.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c5dfee1ba7---8963381736.pdfIn PDF document text
    • http://chatsworth72.com/clients/5/53/532ec3c8dc0e95779814939736d4df6d/File/62223314913.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/b8af02d262e1eb46d4fcf3243ac6bd40/kumowidujebasibeduv.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ba82be91117---fomuxujakakulolalufo.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/m10ocm4q3a3be1i478k1dmi0kl/47034925920.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/fitapinatadaran.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a055f24c922---gilobezoxu.pdfIn PDF document text
    • http://edu-tur.ru/userfiles/file/28875632468.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/xusoputegitizowuvasudi.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16084e27c250ea---bepebufajusesuvezuxi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD95 2960 bytes
SHA-256: 9e8301a812e0963997f2c69c75bfd39e7fcc44359b8a43baf6657440e065e79d
font_01_sfnt_off0000d805.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD805 4956 bytes
SHA-256: fd0b1eedaf47e7be20cab98afa3af1164c57ac276c678a0c7d7b85aeac4ebd4d
font_02_sfnt_off0000e8f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F5 19160 bytes
SHA-256: 14504bbd0df6dfdf9d3ce3539415bf3077911e9f5b5d075c89ad5929e7cf54b3