Malicious PDF — malware analysis report

Static analysis result for SHA-256 51ebb42fa8f0a52d…

MALICIOUS

PDF

79.5 KB Created: 2021-10-09 14:51:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: e5ba44874436b0b2583bdd3447b89843 SHA-1: 5e58cbe5d9458b09b01426755c1daec70c40c6ac SHA-256: 51ebb42fa8f0a52dd3931d725c1d282f51cc2202b2620ced0a85aceff579b9b3
156 Risk Score

Malware Insights

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

The PDF contains a link farm, with many URLs pointing to potentially compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d19689a0f---xosebizunemononodudojoju.pdf In PDF document text
    • http://downtowncincyhotels.com/core_degree/admin/images/cms_imagesfiles/99387476849.pdfIn PDF document text
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/bulukefukujubipowudefuwa.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/29rhoa8ejusaq9kdu45vgva53f/zibodajom.pdfIn PDF document text
    • http://speckrepeg.by/UserFiles/files/wipadopejubigilowow.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/95815288505.pdfIn PDF document text
    • http://eatoceanic.iorderfoods.com/uploads/files/13467711711.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/15939260436.pdfIn PDF document text
    • http://quanhoangtsi.com/upload/quangtri/files/wivoraruribewelopow.pdfIn PDF document text
    • http://yisin.tw/userfiles/file/14366718983.pdfIn PDF document text
    • https://miguktour.com/FileData/ckfinder/files/20210929_90609AF6F88970EF.pdfIn PDF document text
    • http://xn--80aejmo0alc.xn--p1ai/ckfinder/userfiles/files/lokix.pdfIn PDF document text
    • https://preciseenergygroup.com/media/88295673360.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/xaxapiv.pdfIn PDF document text
    • https://servauto.fr/img/user/file/dulakumoratazuwegapu.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/61339225583.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/logojexodumibupenikoxuvaw.pdfIn PDF document text
    • http://tindangnhadat.vn/upload/files/45609422434.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/nipekobozutanaketivo.pdfIn PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/0a6c922754129019b92e3d817f634fb5/90102678825.pdfIn PDF document text
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/47664263179.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/kebesezavewulupisepi.pdfIn PDF document text
    • http://erfanekeshmiri.ir/userfiles/file/tuwubuxuradodujukat.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f33706d7a3---kekatakuxuwomitajeresu.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/20799178950.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=lord+shiva+family+photos+wallpapersPDF 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_off0000ce02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE02 10880 bytes
SHA-256: 38c17f792a7ebc4d49e1256a256e250729c8c555eb5c52870a62bad8531943c4
font_01_sfnt_off0000e742.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE742 18360 bytes
SHA-256: deeedf8f971b563f811c04a8e91273950a6f48547c1d6d87d4799c355f0faf00
font_02_sfnt_off0001166d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1