Malicious PDF — malware analysis report

Static analysis result for SHA-256 87510ba4ad45589c…

MALICIOUS

PDF

83.6 KB Created: 2021-09-15 09:10:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b9628dc9b471ae07d8c534889cc6aa9a SHA-1: 0c3c8252c4bcaefbf6f1c9964aba9f4eb87f3332 SHA-256: 87510ba4ad45589ca712555c444cb7734d422c280284e34f27dd367a4f45de99
156 Risk Score

Malware Insights

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

The PDF document contains numerous links, many pointing to compromised or disposable hosting, indicative of a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and AV detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://www.physedu.in/newsite/userfiles/files/60184608175.pdf In PDF document text
    • http://makinsushi.com/uploads/files/10660611296.pdfIn PDF document text
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/55165217621.pdfIn PDF document text
    • http://hepiran.com/cache/fck_files/file/dogakofinujokisur.pdfIn PDF document text
    • https://tsafar.ir/basefile/tsafarir/files/wusofisojasalaguvonu.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/35156754537.pdfIn PDF document text
    • http://intersonik.eu/upload/files/jugokutejodivag.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/zutunufebikuxifo.pdfIn PDF document text
    • http://ibnuaffan.com/ckfinder/userfiles/files/98836516830.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/acih2uhs35tqejj5btbnk26dmt/47595608299.pdfIn PDF document text
    • http://nghieuphong.com/upload/files/63271700730.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/dixir.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/ar85hatjh9nra0s98hnl0bo3cm/14131680542.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-5/20210905095159447530.pdfIn PDF document text
    • https://canionglobal.com/FCKeditor/file/81574184352.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/41294304503.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021091216474673499.pdfIn PDF document text
    • http://gmicropilotes.com/uploads/files/50554291490.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161392b4023301---xuvigoxaguv.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/nilewo.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614110ee17091---roxuk.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/52210520482.pdfIn PDF document text
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gipetowomifagetal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=outlook+exchange+for+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_off0000dfff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFF 10904 bytes
SHA-256: 57ec924888b16f4057d3f2f6daf768d763682a6f6a35559aab8cf4639eb781b2
font_01_sfnt_off0000f904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF904 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11116 18392 bytes
SHA-256: 9128476ed221e463475566e8f0395b80b5f35119093678d5622dc3b107314ef2