Malicious PDF — malware analysis report

Static analysis result for SHA-256 771d5a9f03e0bbbf…

MALICIOUS

PDF

79.0 KB Created: 2021-07-04 00:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7af65fb81b3e8208c4120aa770a88380 SHA-1: 244aa4b813891953e1ff6821697f41315c1bc77f SHA-256: 771d5a9f03e0bbbf7caeb6309538ae2a14331269ea6ded5f4b1f95ba2d1f96ef
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9844

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://minhledtran.com/luutru/files/gujonifexavuxetikak.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16096486e380e0---posumibefenabasunam.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/cn7b81jsus04as0ojirldd8511/liwoz.pdf
    • http://somersetcountybar.org/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42372992649.pdf
    • http://sosnovgeo.ru/userfiles/file/ragujanexunezitewazoz.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-5-7/20210507015147134197.pdf
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/775e9e896ec47a03924b57645fe3d884/96608775237.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a2d9066d685---tujugur.pdf
    • https://karinbentum.nl/uploads/file/sisoresavevupusi.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160788ae8bd882---patezekekaxut.pdf
    • https://sunnyvale.com/wysiwygfiles/file/50681551745.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/plqvrd9l9dfgq9dask3d4jge33/navuzuwuro.pdf
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/33ae4fd6d6319db61d745c07f0451fdf/midewuf.pdf
    • http://cartopack.com/Images/file/57405230771.pdf
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/e27847a35d0798688dc8f9fa005d6d59/87829063504.pdf
    • https://jagominum.com/contents//files/dadezawirokikegideluxuxo.pdf
    • http://gongotour.com/FileData/ckfinder/files/20210701_EAF9812656BBF9C7.pdf
    • http://clinical-pain.com/pds/userfiles/files/zirariwijofot.pdf
    • https://vhssirimpanam.org/ckfinder/userfiles/files/34290285340.pdf
    • http://scard.vn/app/webroot/uploads/files/towaxufivuxe.pdf
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1bed05997---xoxak.pdf
    • http://martonelektro.hu/files/file/21200706858.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606e2b4b484f6---mezetugonixarexapop.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ccefef4b195---36497046755.pdf
    • http://africansafaris-spain.com/FCKeditor/editor/filemanager/connectors/php/connector.php?Command=FileUpload&Type=File&CurrentFolder=%2Ffile/91197128965.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/325a6bf95d60a6eec343d4520cbc3709/xetotada.pdf
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/mubimufejipulekuradin.pdf
    • http://aihyang.com/userfiles/file/9274818005.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=bnp+and+troponin+in+pulmonary+embolism
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d19c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD19C 16792 bytes
font_01_sfnt_off0000e9b3.bin
3904eacb37d4cc256d266128d8cb3f7f7d1576d7f570516825d78ba435cd4bd7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B3 10960 bytes
font_02_sfnt_off000102e7.bin
54e080f2c794c956a7da80cb447b84028f4380df2ff7ff4fad978d5e12af93b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x102E7 16620 bytes