Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd025419c53d76c2…

MALICIOUS

PDF

115.7 KB Created: 2021-09-19 06:12:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a66f69aaac0fd58b5d0e984d9d2d6a8e SHA-1: 748f7bcbd803deecc682ca729bfe1e49976e5787 SHA-256: dd025419c53d76c26d4a5168d379980d9dd8250243ffbdb905c394c5750d3d83
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to potentially compromised websites or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF functions as a link farm. The primary purpose appears to be redirecting users to other malicious content, likely for SEO poisoning or to distribute further malware, rather than containing a direct exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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://locoffice.ru/userfiles/file/99176001855.pdf In PDF document text
    • https://bocrangsuthammy.vn/upload/files/labozuraje.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/niminuti.pdfIn PDF document text
    • http://safires.cz/ckfinder/userfiles/files/satilatufumax.pdfIn PDF document text
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/27250604714.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/savupivamesazazari.pdfIn PDF document text
    • http://www.jucadent.es/ckfinder/userfiles/files/wefiwigevedozilejezifabi.pdfIn PDF document text
    • http://newgoodluckcrane.com/admin/uploadfiles/file/76476023363.pdfIn PDF document text
    • http://portableandcool.com/files/files/lurudovu.pdfIn PDF document text
    • http://geomanteia.com/userfiles/files/vedalofina.pdfIn PDF document text
    • http://sbkf.org/files/files/64560375755.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/95172947183.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/koripabuxesarewurubome.pdfIn PDF document text
    • http://kindergartenhelden.at/upload/file/7258875835.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/mukiwim.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/16139a3557123a---1969238971.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/nmbjbo6qdmkkv0u5o56811q6km/22735042755.pdfIn PDF document text
    • http://dominant.name/userfiles/file/6824782305.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/64318999451.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141e0d0810ec---vekibijefaka.pdfIn PDF document text
    • http://nomayaku.com/userfiles/file/78782718270.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/161448ec36024e---64692322110.pdfIn PDF document text
    • http://www.kigimex.com.vn/ckfinder/userfiles/files/46975897161.pdfIn PDF document text
    • http://pro-group.ru/userfiles/files/wuselisilapab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=head+first+android+development+3rd+edition+pdf+free+downloadPDF 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_off000156cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156CD 21020 bytes
SHA-256: 540edcabbb487480e95cde33bcc1adde5591062c6358a449a0e1b600b0e22ba7
font_01_sfnt_off00018f00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18F00 10972 bytes
SHA-256: 5871bae44d6cab7fc91302f11e32167066c16968c2ebd10740b04346454cd4fb
font_02_sfnt_off0001a878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A878 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1