Malicious PDF — malware analysis report

Static analysis result for SHA-256 397cf5f08a1efccf…

MALICIOUS

PDF

73.3 KB Created: 2021-10-12 10:17:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dddf92bf16d0d436ed2c33d0d44bf59a SHA-1: 1836e286ebda6e19f8af8cd2438cbf95b07f2caa SHA-256: 397cf5f08a1efccf3bb7b978e37dcd7c035ad70a45d9ca7d2494c91794a38b4e
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm designed to host or redirect to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the rationale is based on the heuristic findings and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16149c9ae2ae26---43130642733.pdf In PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/161454f59b9205---xejiratejaxosesiramebeko.pdfIn PDF document text
    • http://gaushalango.com/uploaded_files/userfiles/files/55045611732.pdfIn PDF document text
    • http://uni-soar.com/userfiles/file/rojotuziwugin.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/28605472740.pdfIn PDF document text
    • http://ovecollection.com/royal/admin/images/products/file/jegona.pdfIn PDF document text
    • http://www.f2dassociates.com/userfiles/file/botovagatoxeterujisurut.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/41543691819.pdfIn PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/19207234355.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/161419cd08f12c---2935620753.pdfIn PDF document text
    • http://newshop.jp/archive/file/18280076447.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/pomaxe.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/51550220295.pdfIn PDF document text
    • http://olapromos.com/ola/uploads/editorImagesfiles/32927116849.pdfIn PDF document text
    • https://sassanoproperties.com/FCKeditor/file/fubotasonivagegexenotef.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/tobivovenuzugedulenamu.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/10157685632.pdfIn PDF document text
    • http://lnianemarzenie.pl/userfiles/file/30049577293.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16163dd8a94143---98135561036.pdfIn PDF document text
    • http://hig-hegmann.de/userfiles/file/48941231868.pdfIn PDF document text
    • https://lighthousemacau.com/html_upload/file/89042454263.pdfIn PDF document text
    • https://marwaautorepair.com/nbloom/fckuploads/file/goxubebow.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/xofafek.pdfIn PDF document text
    • https://chungangroup.com/uploads/files/202109281653024776.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/68813292471.pdfIn PDF document text
    • http://tingchucontrol.com/Uploadfiles/files/95625824515.pdfIn PDF document text
    • https://yantrasearch.com/ckfinder/userfiles/files/julenanowigagesikazo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/UsNeCLCzgYg/uplcv?utm_term=user+friendly+meaningPDF 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_off0000bd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2C 10600 bytes
SHA-256: 35545591f6c091a1a1889233d8f5a609f436e170ba0cca3f08c5d15be05baa8d
font_01_sfnt_off0000d519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD519 16692 bytes
SHA-256: 7ec2458d8e30fada4423770f66e7ecd912dc80705ca56699baa8646eadd497e4
font_02_sfnt_off0000ffe2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1