Malicious PDF — malware analysis report

Static analysis result for SHA-256 550a77a23ef9bc2a…

MALICIOUS

PDF

75.4 KB Created: 2021-09-20 18:56:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 59f343a1ab21af2e5e7eff9508c11337 SHA-1: 90fe062aac6b2781532936cf79d76877e8259c77 SHA-256: 550a77a23ef9bc2a05652ce3c9ab260afb99966dcce67c70a2e4aad0ad53001e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to obscure the final destination. The presence of these links and the overall structure are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://agataklimowska.pl/userfiles/file/judutowagakufop.pdf In PDF document text
    • http://ettermanenterprises.com/ckfinder/userfiles/files/34322229645.pdfIn PDF document text
    • https://bazab.ru/ckfinder/userfiles/files/22827985297.pdfIn PDF document text
    • http://besteva.com/upload/files/potelidude.pdfIn PDF document text
    • http://productinfo.in/konadnew/userfiles/file/wegapediwuvopeg.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142dfbf5c029---sibonugekumaru.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9ef8a39da---xedekagubogejatu.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140fddf420f6---81561002341.pdfIn PDF document text
    • https://vargyasnekonyveles.hu/kepek/other/file/xezozajirarokufekudusebid.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/15312928059.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/zubafot.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/tovowagojaxovizojizugu.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/jarefotixe.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/161343cd41b675---pivizes.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/xasalunu.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/vebirutobul.pdfIn PDF document text
    • http://feldbach-tourismus.at/files/foguwobedovipejoz.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/u6opr3q2ur2ge4psvdkneckbek/65996991139.pdfIn PDF document text
    • https://myshalewell.com/userfiles/file/36349478616.pdfIn PDF document text
    • https://mvpartners.be/images/uploadedimages/file/makuzubopinegilox.pdfIn PDF document text
    • http://ladyvenus.it/userfiles/files/82299696256.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=apk+without+license+verificationPDF 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_off0000c14d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC14D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d95f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95F 17832 bytes
SHA-256: 2abf753d7b081457db015069088b17bd00a68cc1f3e186c1de2665fc42064e79
font_02_sfnt_off0001072f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072F 10904 bytes
SHA-256: 6f5b538ae77f0bf61c8f2469072be1f673a545de8de216f9db385809922815c7