Malicious PDF — malware analysis report

Static analysis result for SHA-256 81f6bdc91c4dc991…

MALICIOUS

PDF

84.7 KB Created: 2021-09-02 00:24:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 2c2ae30af3371afebde479dbeb181645 SHA-1: 1af20de515a3179d69151919c173d14def3e3826 SHA-256: 81f6bdc91c4dc991975f1e549c6b6df07d5d5f18157406449c5c22966c89d19a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm directing users to multiple external URLs, with several hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL analysis point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://soechi.com/userfiles/file/kilitolituze.pdf In PDF document text
    • https://remini.hu/userfiles/file/lefovereru.pdfIn PDF document text
    • https://hitourkorea.com/FileData/ckfinder/files/20210826_5A548090DBEACAEA.pdfIn PDF document text
    • http://sassyissy.com/survey/userfiles/files/jijilupivumopijixegora.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/3021a89c89e9823d6728f3d832af15aa/fenevezorazagixog.pdfIn PDF document text
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160715f44ad7de---surosa.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/439dd4225ce8c20ae12ea25e7fb93fb3/10484367764.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/monogerovugakezawuze.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/74091595303.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/buviv.pdfIn PDF document text
    • http://beachfirebrands.com/userfiles/file/kigiwizowex.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/68524117533.pdfIn PDF document text
    • http://brette-animation.com/userfiles/file/tixuzaruwawewukuvej.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609a71fe42b67---luvusejotuwuveden.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/tobanapexamuzemizaned.pdfIn PDF document text
    • http://atomicattack.com/atomic/fckimages/file/11730536121.pdfIn PDF document text
    • http://cuacuongiare.vn/upload/files/20188350886.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/61018222086.pdfIn PDF document text
    • https://curvy.tw/upload/files/buzufuzisovamijibixaweg.pdfIn PDF document text
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/aj2pk7ieh64cgkfl7h9khnngk4/11481086372.pdfIn PDF document text
    • https://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/91526749520.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/61436186976.pdfIn PDF document text
    • https://nidi.mk/ckfinder/userfiles/files/74549237814.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/falavusubibobunowesaso.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+open+garage+door+when+power+goes+outPDF 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_off0000e770.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE770 17016 bytes
SHA-256: aae292ce65e19a0e82577e2e0db013afe174c93e43edcf57adb5f88737d9fccc
font_01_sfnt_off0001134d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1134D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B64 10712 bytes
SHA-256: 7339e7b259160e31fcd324c2a6dd434094607c5b65246b28c3b384226c3870f9