Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cf0356a8e707f8e…

MALICIOUS

PDF

84.0 KB Created: 2021-09-18 11:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8e3384c211cb65a8d9ea678d02f72c53 SHA-1: 3de0b809c0b83b5eb90fd0610786444c63b4964e SHA-256: 1cf0356a8e707f8e5c4e19d25a48a2674eb5837bbeba24d81eb4dbf7201e31b4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs, many of which are hosted on disposable domains and appear to form a link farm. The presence of embedded JavaScript and a high ML classifier score, along with ClamAV detection as 'Pdf.Phishing.Trojan', strongly suggests a malicious intent to redirect users to potentially harmful content. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://maiodi.com/userfiles/files/mekibudeloxal.pdf
    • http://sowiik.pl/userfiles/file/59315622045.pdf
    • http://apvn.info/userfiles/file/79338730711.pdf
    • http://apartamentykunickiego.pl/architekci/public/upload/ckfinder/userfiles/files/wuwilijatojet.pdf
    • https://u-spot.biz/js/ckfinder/userfiles/files/bebibin.pdf
    • http://sensi-leszno.pl/userfiles/file/kelovutudurakamuwiredo.pdf
    • http://packamate.com/userfiles/fanebowadogugatax.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f27b00c431---46421987300.pdf
    • http://stressmanagement-karriere.de/userfiles/file/53537258501.pdf
    • https://walkandsmile.com/userfiles/file/gulezixaxoj.pdf
    • http://isagenixmakessense.com/ckfinder/userfiles/files/sojedubokab.pdf
    • http://galantemontagnana.it/ckfinder/userfiles/files/mebazujuvuju.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/rokflhal1m1j1mug26hobk4i9o/72314955814.pdf
    • https://alperbehang.nl/userfiles/file/66936913167.pdf
    • http://www.frank-diagn.hu/userfiles/files/23271735319.pdf
    • http://sethhukumchandschool.com/userfiles/file/6900518189.pdf
    • https://yarpaket.ru/userfiles/file/nupapilokavesa.pdf
    • https://kenhquangcao.vn/uploads/files/4283589205.pdf
    • https://tennis94.fr/img/pics/files/xadinutixomopivefud.pdf
    • http://solarexperten.ch/fckeditor/editor/images/file/dokozisuvexe.pdf
    • http://upasamed.org/Content/uploads/files/559713727.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/161350826032f6---dosedugudikikonimarokepur.pdf
    • https://granitabrasive.ro/editor_up/fepumibi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=18+wheeler+arcade
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df4f.bin
b7a653a60a45788851262bafc6e3f47941e753092077156b1d168fc0c050452e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4F 10136 bytes
font_01_sfnt_off0000f62f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF62F 16792 bytes
font_02_sfnt_off00010e41.bin
cc2033bd6d79925957da03e529b194169d828274069c1e675b0d7e6f255c1c37
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E41 19844 bytes