Malicious PDF — malware analysis report

Static analysis result for SHA-256 3439a53c6f545d37…

MALICIOUS

PDF

74.4 KB Created: 2021-09-03 08:27:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ede85fad3b88e17492cacfba8274f1ba SHA-1: 0c237007e8a31ac5ac72218ecff111aec8661e63 SHA-256: 3439a53c6f545d3775d14cd46134d2746e752fa3c7b23cd721b6d72c090178cf
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a link farm pointing to numerous external URLs, many hosted on compromised CMS upload directories or disposable domains. These links are likely used to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://vedepcuaem.com/luutru/files/26779405886.pdf In PDF document text
    • https://teenvolunteerhouston.org/wp-content/plugins/super-forms/uploads/php/files/0e850f38b37ab01fa6bbb9c263c16143/88354949101.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/30324556227.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/6706759672.pdfIn PDF document text
    • http://burfel.ru/upfiles/files/teledezore.pdfIn PDF document text
    • https://reparation-mobile.net/userfiles/file/karok.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/kawejefavuliwibegutelewu.pdfIn PDF document text
    • http://bensonhigh67.com/clients/55910/File/20162085002.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/1e16a756b688a586daf87b30018dc1d2/vopabujoviri.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/refosiki.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/38573243906.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/eju3uov15rl0othlfqmla22qg8/95611571923.pdfIn PDF document text
    • http://trineckevzdelavani.cz/webpagebuilder/ckfinder/userfiles/files/95054245369.pdfIn PDF document text
    • https://drproperty.in/userfiles/file/91779344859.pdfIn PDF document text
    • http://nicenpos.com/userData/board/file/2179750343.pdfIn PDF document text
    • http://ceomit.com/fckupload/file/35604620706.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/pozoremiluvodedufubiboru.pdfIn PDF document text
    • http://www.darvidproperty.com/news/file/30839797214.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/99241481076.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/mamivobugekuwamir.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/c5656e54635ccecdda9bd9d8cc691995/dizoson.pdfIn PDF document text
    • http://ateliergermain.net/sites/default/files/file/33401525013.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/wezenobajixak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=patologija+moci+pdfPDF 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_off0000be75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE75 10588 bytes
SHA-256: 3655c3e8b456fb853c4e480af774e94092e45fe2d518bfdee48ca7fab76b1842
font_01_sfnt_off0000d66e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD66E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE80 17824 bytes
SHA-256: 8a189d5cf0bccf0f769dc15020fab547cb63f56cedf60ae30377e136065f5308