Malicious PDF — malware analysis report

Static analysis result for SHA-256 56f1b44abffffc4b…

MALICIOUS

PDF

81.4 KB Created: 2021-09-16 20:29:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 18b37a997384e6bbb3f909ca04e541cb SHA-1: 719b02da7971690487c5ae2dfbcf37740766f908 SHA-256: 56f1b44abffffc4b1fd27b6ea4a35549d1cd589685f27f6ba09a96cbb2f68dad
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to link farms hosted on various domains, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious documents that leverage embedded JavaScript for exploitation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://eachfun.com/ckfinder/userfiles/site_eachfun_com/files/jaxufubugisutefenodo.pdf In PDF document text
    • https://legend-chang.com/UserFiles/files/89116687818.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/15420498526.pdfIn PDF document text
    • https://waxparadise.pl/userfiles/file/74655343603.pdfIn PDF document text
    • https://magnettoptan.com/upload/ckfinder/files/jufitodumoruduvemekelel.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614136f57bf73---lezuxevedededubijexevu.pdfIn PDF document text
    • http://kerekesvillszer.hu/UserFiles/file/famuxerogogep.pdfIn PDF document text
    • http://theurbanbazzaar.com/userfiles/file/4701772818.pdfIn PDF document text
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/30981935933.pdfIn PDF document text
    • https://www.bakkersvlaanderen.be/resources/plugins/ckfinder/userfiles/0/files/31468684346.pdfIn PDF document text
    • http://americasbestwingsbeltsville.com/uploads/files/12341033457.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614366c9d9c0d---jolovifu.pdfIn PDF document text
    • http://azco.friend-match.com/upload/files/9017216620.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/wiwuf.pdfIn PDF document text
    • http://aguito.madteam.net/ckfinder/userfiles/files/ludivosolu.pdfIn PDF document text
    • http://melly-incendie.fr/img_db/bemewizijiwitovataloda.pdfIn PDF document text
    • http://virus-safe-zone.com/ckupload/files/babub.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/watipusejub.pdfIn PDF document text
    • http://qbcar.ru/ckfinder/userfiles/files/66691078526.pdfIn PDF document text
    • https://nullemont.fr/nullemont/ckfinder/userfiles/files/59204120478.pdfIn PDF document text
    • https://awinresource.com/uploadfile/file/fitatateralodenu.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/16232176108.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/fezudun.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=linux+pour+androidPDF 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_off0000d886.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD886 19672 bytes
SHA-256: 18c9614a38e2a143c9d1bc8294fb0dd24fd629211785dd9a45edfb548d421a6a
font_01_sfnt_off000109c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C6 10100 bytes
SHA-256: 937d4fe29eea396ade01937b93dc6e973e142b56a04cf1f0639d8ba8f5630f6b
font_02_sfnt_off0001204a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1204A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1