Malicious PDF — malware analysis report

Static analysis result for SHA-256 083218a24b3ab591…

MALICIOUS

PDF

76.5 KB Created: 2021-09-01 10:26:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c9f746caf2fb6f4c0f99809efea3d649 SHA-1: c9f079d41dc3e6443c38cc475cbfba1d5f83b4d3 SHA-256: 083218a24b3ab5917d2b1cb996eb9fb08b9e31b1b4201ca2f07e0fd849cc774b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for executing malicious code. Several heuristics indicate the presence of link farms pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to distribute further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/1607325c7e147d---damuve.pdf In PDF document text
    • http://portableandcool.com/files/files/noxizefuwiwunovagot.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/5180850097.pdfIn PDF document text
    • https://semangkamerah.com/contents/files/fewetusog.pdfIn PDF document text
    • http://thepnguyentran.vn/media/ftp/file/71857115041.pdfIn PDF document text
    • https://grandhotelbulgaria.com/userfiles/file/vatukanaforisor.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/roverujadukafox.pdfIn PDF document text
    • http://vanlysecurity.vn/vanly/album/files/26495872329.pdfIn PDF document text
    • http://3mfa.com/images/editor/files/lamomuzuvakesafefosen.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/goxigixuwejodupowosa.pdfIn PDF document text
    • https://www.lavishlook.se/wp-content/plugins/super-forms/uploads/php/files/b6e808fd4dceb99be975fb81e1cfa0dc/26398296756.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eca3c4523c---nimujipemi.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/nemovulimijagizamon.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/81341b4351946beb94c9a6f463282b8d/nibexuxuja.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/64339980983.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160edbee535366---36840299239.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/uj6pp4j5fisiv4evbmehimcj8q/83493705077.pdfIn PDF document text
    • https://endoaccessories.com/wp-content/plugins/super-forms/uploads/php/files/0fo5hej356leo80dpeveosv8c0/wodozajexevir.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/a3c914f641ffa126f61679eb92955f3c/ferewu.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/posiwidorumivil.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf9c13f651---pajibajusirukigoforenimid.pdfIn PDF document text
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/f47aa08389f7e725cadbad033900a831/48717947700.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/sekajasa.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/39305e63feda264948f920303c3d6047/51501644834.pdfIn PDF document text
    • http://evergreendentistryva.com/app/webroot/js/ckfinder/userfiles/files/wawitorureleludumivem.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=adding+and+subtracting+integers+maze+answersPDF 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_off0000c572.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC572 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD84 17428 bytes
SHA-256: 6043b32a8ad04c0db9243a8c958da8ce781c217f45524e01ec9dd00b3d79664d
font_02_sfnt_off00010a5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5F 10916 bytes
SHA-256: 592635ce150bee7c9a6846d6ce91ac9e2d46070289333dd353c0ad0370666454