Malicious PDF — malware analysis report

Static analysis result for SHA-256 27bfe2d014854b16…

MALICIOUS

PDF

88.1 KB Created: 2021-09-08 18:00:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0b5ba27b40f0475df5aebd1757532486 SHA-1: 67424b62063c38b81b810a4effd4f200cb768572 SHA-256: 27bfe2d014854b168705bb7049de9cac044e355d33a81b62693035a865540db1
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified the PDF as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, while numerous, do not appear to be directly executable, but their presence on compromised or disposable domains is suspicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://studiobaliva.eu/userfiles/files/89950881436.pdf In PDF document text
    • https://bakwanudang.com/contents/files/12378799931.pdfIn PDF document text
    • http://tscyw.net/userfiles/file/20210907211026_brfmsu.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/96899677307.pdfIn PDF document text
    • https://8cj2aja7-8mxb.com/contents/files/ridor.pdfIn PDF document text
    • http://prestopc.it/upload/file/66531187569.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/161387499c894d---welidoson.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/b90d6d899863186ca98c3343e9a506fe/61365957695.pdfIn PDF document text
    • http://dakmoto.cz/obrazky/file/movanuv.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/61350791c5317.pdfIn PDF document text
    • http://opsir.eu/files/file/38206165485.pdfIn PDF document text
    • https://czus-lukasa.sk/userfiles/file/katewanejuxelapokune.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/27e03e1c96a6fc4280354bdd6599ba25/8865658345.pdfIn PDF document text
    • https://knoxvilleremembers.com/media/zanovovabubikuromufoveju.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/ginefavejin.pdfIn PDF document text
    • https://alpinashop.bg/files/46544029275.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/24481460094.pdfIn PDF document text
    • http://xn--80aggmy8c6c.net/UserFiles/File/zuvukezaligegifibazuzowu.pdfIn PDF document text
    • http://snieznik.pl/userfiles/file/42866476300.pdfIn PDF document text
    • http://giaodantanthaison.com/Images_upload/files/fojeluteragutuwagu.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16132a04aa1268---bugagikolapodasamijo.pdfIn PDF document text
    • https://tch.lu/files/files/55322653817.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=linux+command+line+pdf+to+pngPDF 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_off0000f1e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E7 18324 bytes
SHA-256: 31385b166e71b758a6c9859258ecbeb837632133fb6a2c1337b176397b25161b
font_01_sfnt_off000121e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000139fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139FD 10856 bytes
SHA-256: 1e7004d2bec5dd62ebdbd59350710cd51c502ac697caf7905d0e156fae6bd56f