Malicious PDF — malware analysis report

Static analysis result for SHA-256 b838a6c03ecfc139…

MALICIOUS

PDF

88.3 KB Created: 2021-07-18 15:42:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: c2ea48a13130a9a750b65e762eda6da7 SHA-1: 4b0f8ea3ae8baf84a98ec644a857e13ea56cb11f SHA-256: b838a6c03ecfc1391dc967bf3467648f6fa7b3d88801072558adf31856ea335e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the PDF contains a link farm pointing to compromised WordPress upload storage, suggesting a phishing or malware distribution scheme. The presence of multiple unknown URLs further supports this, as they likely serve as landing pages for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e3439089d---58842465930.pdf In PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/eab40d3a2c3d1ab0a00a9159f09b7f0d/66754397982.pdfIn PDF document text
    • https://ngusacdon.com/upload/files/nokedez.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/4948cbbcc566692d099afef6c4bd868a/95862192362.pdfIn PDF document text
    • http://www.orarestauratorisaf.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e0a1b649ef2---97504470101.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a13a4536f19---xosivotizarifaj.pdfIn PDF document text
    • https://canevastoilestjean.com/upload/editor/file/kivomuwunafulipobakiwus.pdfIn PDF document text
    • http://fenotropil.ru/userfiles/file/wunojor.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/4626e3a7c7ad9b1b0f5db8adc25582a9/27912602632.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ddd6dde896f---lofukijugatesiseto.pdfIn PDF document text
    • http://clintonseniorhighclassof77.com/clients/e/ec/ec6cde7faca09d53f5ba1fe44cd32e38/File/tupesifofanemevazusese.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/48730969617.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/fsqjl5udc09mfoo5m0v0jnjat5/tuvowaniwesomo.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/gojupekefiririnas.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d511d9169c5---49420349577.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d885a04f49---36041326556.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/powonawevevemanidev.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092c0924f1f4---bugonal.pdfIn PDF document text
    • http://jeyadhurgatemple.com/userfiles/file/98962639335.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/2b0bf390313a62364ab6b53ea0b8e8a7/15566858976.pdfIn PDF document text
    • http://shophouse.info/images/files/bizaxizulifekefaku.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/t9el29j8098nuloeon8do1b9i2/wokedugirotowamis.pdfIn PDF document text
    • http://ekotop.eu/userfiles/file/pulonaperisufupususin.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6f0a130cf---jabutinagijugupix.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb82de657b.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=hero+system+6th+edition+pdf+downloadPDF 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_off0000f521.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF521 17036 bytes
SHA-256: 22f01de26f56e34ae5c3057292cd956ee934560b79a723bf3ea4744fe90ada29
font_01_sfnt_off000121f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F0 11124 bytes
SHA-256: f13cc74d278bb802419be1e18c7388f818458a85942835884b279c401b60df02
font_02_sfnt_off00013bcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BCB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1