Malicious PDF — malware analysis report

Static analysis result for SHA-256 c52607ba9bfa1acd…

MALICIOUS

PDF

82.9 KB Created: 2021-09-09 00:05:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8e5e0599ab502a0d7297eba7d1e9a59c SHA-1: 109858897792478fd8cb3d407dc8d9b0114dd191 SHA-256: c52607ba9bfa1acd5db2c8cca2808469ae8ecb5d0336c34b04c5eba15cbfa9ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to lure victims to malicious websites, likely for phishing or malware distribution, aligning with the Spearphishing Attachment technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff52c56184---19720889174.pdf In PDF document text
    • http://xn--9i1b14lwsg1seumdzsx.com/upload/fckeditor/file/bexuma.pdfIn PDF document text
    • https://faktxeber.ru/resimler/files/25000123850.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/wukakemaw.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/95900920339.pdfIn PDF document text
    • http://fotofolliasanlazzaro.it/userfiles/files/79926931451.pdfIn PDF document text
    • https://robertbah.si/files/file/gajekebanonapon.pdfIn PDF document text
    • http://lgassociates.in/uploads/77035741865.pdfIn PDF document text
    • http://fine-trading-knotwork.com/uploads/media/56860687065.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/uh5tt9qk60oqrbi3obec1f24e5/murolexaxujumorifedut.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16132cf255b824---pupukodefutowi.pdfIn PDF document text
    • http://tuvanthanhlapcongty.biz/upload/ck/files/16570677238.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/jopuf.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/18530720567.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613924a7bc73c---51203979262.pdfIn PDF document text
    • http://df-2.de/images/daten/file/dexijafadepotuna.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/161319d60c653d---sokazebamafuza.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/85794819379.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/90702381596.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210907094908946.pdfIn PDF document text
    • http://www.musicboxpiano.com/contentfiles/migepumiwejalalivisi.pdfIn PDF document text
    • https://jagamimpi.net/contents/files/wisumerupebegugitewe.pdfIn PDF document text
    • https://coil.hk/upload/files/74829466720.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16135c8ef8bd54---buwixutotajexefesoki.pdfIn PDF document text
    • http://sintniklaas.kinderopvangpimpeloentje.be/ckfinder/userfiles/files/54919992840.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=android+messages+for+iphonePDF 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_off0000e1b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B2 16728 bytes
SHA-256: 0b21224ecbfd8a97bf096b036d0296a8ae65f57da5b9a158eddcc456c74f4720
font_01_sfnt_off00010d2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012541.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12541 10784 bytes
SHA-256: f12b55421bcfc63df0ea861c4d39ffdb442804c65ed087643fce3e90fa00ecbd