Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc7cbc81365adbc8…

MALICIOUS

PDF

81.0 KB Created: 2021-09-12 19:37:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5eec8c7a0a15f916715ed22cbce734bf SHA-1: e3b8a158fae832ef3f2d880b75b7a50d3cb431aa SHA-256: bc7cbc81365adbc8153c9eefbb1aac667b6d067e067b4ea8dfcd4972d15e193d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected by ClamAV as a phishing trojan. It contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. Furthermore, the file exhibits characteristics of a link farm, with numerous URLs pointing to compromised WordPress upload directories, suggesting an attempt to distribute further malicious content or redirect users to phishing sites. The presence of embedded JavaScript and the link farm structure strongly indicate a malicious intent to compromise the user.

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 https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16136dc21b3a54---21434283110.pdf
    • http://mundori.com/js/ckfinder/userfiles/files/49778974179.pdf
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/58857765846.pdf
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/94194764424.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/qo2r91ap9kq9o13g048g7tge1n/nitabuxep.pdf
    • http://resortcrimea.com/ckfinder/userfiles/files/59804347117.pdf
    • https://gym-rectif.fr/ckfinder/userfiles/files/sotatulejezi.pdf
    • https://rendszergazda-cegeknek.hu/ckfinder/userfiles/files/42271129887.pdf
    • http://kencert.vn/uploads/image/files/kilobiwufeguzewoxona.pdf
    • http://velapower.com/glwh/UploadFile/file/2021090522453273499.pdf
    • http://askort.pl/Upload/file/6979934900.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/dbc2753125241006f2fb53670df761b4/51693096910.pdf
    • https://kaimano.it/file/66999402267.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16138605d8c613---30722650016.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/ed1mgmnsj8uj0hc6fq5jvdsgh7/69869342969.pdf
    • http://wawabed.pl/uploads/userfiles/file/saguniwijeniwoputitorilam.pdf
    • http://pscemetery.com/userfiles/file/89487908096.pdf
    • http://abwnickersonplaza.com/uploads/files/36193191084.pdf
    • https://fulzugaskozpont.hu/files/59265740795.pdf
    • http://golden-candies.ru/webroot/files/files/83664072584.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/94e3ec01387f63ae1284e9188e8950ce/12904352754.pdf
    • http://uro-medical.pl/zdjecia/fotki/file/48367000466.pdf
    • http://elcampoeco.org/FCKeditor/file/98331822069.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=shortcut+to+website+on+android
    • 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_off0000d5ff.bin
8bbe54d15b65d69937538ca86125d16c58b83d959b6e6e06e16efefbb7f5c92b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5FF 18328 bytes
font_01_sfnt_off0001055a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1055A 16792 bytes
font_02_sfnt_off00011d71.bin
61a35e435351f4b0c958bc8414f26dc0f86b91214b086a591908b5db67487a68
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D71 10820 bytes