Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4cb32912f6a1615…

MALICIOUS

PDF

75.6 KB Created: 2021-09-06 05:15:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ccad5b11aaf50b3cb514159da7df3075 SHA-1: 775cf78cb0488c8d9602a5f80f4dc0c3a2150295 SHA-256: b4cb32912f6a1615059a8f69b7013eeb1426336b1e6f816c11198e832b517d9c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous links to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a phishing or malware distribution vector, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160987497736e7---74013495191.pdf In PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/2si7mahokh9lvfi6ntd09jam4v/35558953433.pdfIn PDF document text
    • https://igruppe.no/ckfinder/userfiles//files/41893465921.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16106df39db066---xejofarojerefakifuzanab.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca14d0fa16---73203494126.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b077ab71d1f---pekevefo.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/4c8f1086517f86e175291e46bd9055dd/rabemifebagizebare.pdfIn PDF document text
    • http://ambvetfanini.eu/userfiles/files/2556282009.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/wapezaxapur.pdfIn PDF document text
    • https://aihr-iadh.org/uploads/FCK_files/file/17647716508.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/tapitupamavodotojabeko.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/kodivozuvobivu.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a06b3edd5---22530310342.pdfIn PDF document text
    • http://www.nomorcantikjoss.com/file/patipuxifatut.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/ebb15e83eebefbdc9d80641681022274/joruxefar.pdfIn PDF document text
    • https://bamor.org/userfiles/file/10743655139.pdfIn PDF document text
    • https://medtek.vn/storage/file/49960726916.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160862962d2f10---71610785953.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/nepari.pdfIn PDF document text
    • http://ty-int.com/files/files/40368842343.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfca009605c---96209623499.pdfIn PDF document text
    • http://kbinteriery.cz/userfiles/file/zenixur.pdfIn PDF document text
    • https://agenciaboom.com/wp-content/plugins/super-forms/uploads/php/files/hc8ll8p94v320ov7i1kqi1acj0/72243674487.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611fa7361a273---61151712498.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=igneous+and+metamorphic+petrology+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_off0000c1e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1E2 11232 bytes
SHA-256: 25238a7471c3d1a34bef3d24b46206b6b8491cd496e9bf940ac8f2a94b48aca0
font_01_sfnt_off0000dbd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD4 17428 bytes
SHA-256: 448e769087d03c0ba7aa6239b7f4ccc155d2aa4e3c2c7cafc84a6253c6b2e22f
font_02_sfnt_off000108d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1