Malicious PDF — malware analysis report

Static analysis result for SHA-256 36a6d043966d3b70…

MALICIOUS

PDF

108.4 KB Created: 2021-07-28 08:19:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 5dec322262feef5070f5fe676eb61d7d SHA-1: efb9a7480162ddae8e6d61865c12e4cee9dae370 SHA-256: 36a6d043966d3b70de60b2c09f4e9f57cf043654ab203c9b5e4f8b5d63adf0b7
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious content. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of these links and the overall structure strongly indicate a phishing or SEO poisoning attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://vannordenvastgoed.nl/userfiles/file/62365015470.pdf In PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a406514b48c---44319744579.pdfIn PDF document text
    • https://aedwea.com/upload/foto/kanejutudobopexuma.pdfIn PDF document text
    • http://odpadykj.cz/UserFiles/File/sadikebigi.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f116c6418---lotogivegidekuvekafufome.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/d58e0c6068cbec424d677edcfc5b083c/kesajezubone.pdfIn PDF document text
    • http://midel.me/userfiles/file/pawoxagap.pdfIn PDF document text
    • http://xn--l3chcucnqd9c0eua7b1k.com/user_img/files/gutazukijorigareniwevaj.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/daxuku.pdfIn PDF document text
    • https://sca-kc.com/scauserfiles/files/mofawowinakokemifa.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/jagoxosetarumozeti.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/f8pf71nsmo5ogumhq0bh4iul4m/sigunobilatotomeva.pdfIn PDF document text
    • http://dachastyle.com/userfiles/file/pololuj.pdfIn PDF document text
    • https://accounting789.com/ThImg/file/665982064.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/dapimoziwinikanubowiwiju.pdfIn PDF document text
    • http://thepokeluau.com/uploads/files/91539961539.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16075874480e69---45163640379.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/2r40ts6mpcs1k9fgm0hvrrqjkd/14385544585.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/dodobimumezagabafudeturo.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e6be5b2de---48698347342.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb41760596---kojelekasi.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/39459758951.pdfIn PDF document text
    • http://cichanski.com/Upload/file/loguzozofuvasoxusoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=calvin+and+hobbes+cartoons+about+schoolPDF 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_off000144f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144F4 10804 bytes
SHA-256: 27c71112e58403fe662214bfcd8ed0107f4caf75808d177f6d9715cf45c21831
font_01_sfnt_off00015dd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15DD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000175e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x175E7 17924 bytes
SHA-256: 127047ea4984640b0266bc18effe5e8ea743d0365d86d78f34b7a8b2772f5d36