Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa4fd843a903b22b…

MALICIOUS

PDF

83.8 KB Created: 2021-08-18 16:45:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: cfdecd62003f72a480307c4f287a816b SHA-1: 62f78afd199ed1972a680d749d2b435e1d07f803 SHA-256: aa4fd843a903b22b64af3c2770854067c57b954bf5a516dedff611c03b1b68e6
156 Risk Score

Malware Insights

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

The PDF document was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. Heuristics indicate it contains a link farm pointing to compromised WordPress upload directories, suggesting an attempt to redirect users to malicious or phishing content. No scripts were extracted, but the structure and URL patterns are consistent with a malicious document designed to exploit user trust.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608a32e565b77---kepuvabos.pdf In PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/tm8n8r0eui4ca4tp6r7vp7e2vm/xabulitunupo.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/161068ef3825dc---87924986992.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/lomikujumodulepizopi.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/d95c1774c05951399c19d3f3fb892317/duxalozifupajaleguboti.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/41774945938.pdfIn PDF document text
    • http://dgjst.com/upfile/file/37181836483.pdfIn PDF document text
    • http://investbuild.ru/var/upload/file/veregil.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/murag.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b41f378906d---19876538190.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bf9bc6bc2df---nopamirobe.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/68261197417.pdfIn PDF document text
    • https://bmw-zona.ru/uploads/file/34837568444.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/efc0652e4e9e6d0dbb4d5da92c548301/56899293154.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/70585619839.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/wigazufogezomagag.pdfIn PDF document text
    • http://feldbach-tourismus.at/files/4170852968.pdfIn PDF document text
    • https://cultureresortpokhara.com/assets/userfiles/files/pesiva.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/57c74d62ab3e9f7045c770b42025cc45/govotujejatemabufesal.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/6075860177.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/70942e822bae436fc801f8c7886fe1bd/2916938895.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/90090256232.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/c29e4c7d3cbfce726d8f8ce462082540/niwatofifubapusa.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/pafujisojesikubanijo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=new+hollywood+hot+movies+list+2018PDF 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_off0000e305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE305 17152 bytes
SHA-256: 06e69be0648e9a49a59bdaa22d0c263b2437d3387fb8c98b2b6395d70dad1801
font_01_sfnt_off00010fb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB9 10892 bytes
SHA-256: c60222af1eb4c4bfe77dc4a8df8671c59a4bf1fbf4f0b468687ae8341e97aa5d
font_02_sfnt_off00012917.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12917 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1