Malicious PDF — malware analysis report

Static analysis result for SHA-256 916ffc8a3465e7f4…

MALICIOUS

PDF

95.4 KB Created: 2021-08-11 08:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dba3196271f9108a6356202ce6d01c5d SHA-1: dae2cfbfd247b21ade531d44e12673332b1991bf SHA-256: 916ffc8a3465e7f490a257932602a87167eab8fb97f709e481d3caac7f35347d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farm heuristics strongly supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://kemxoi.vn/app/webroot/files/images/pages/files/52226460682.pdf In PDF document text
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160ba68d3d65be---totolevisazifiwet.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/ba0aba181fd2fd8c7ba1b1a602be17ca/84317615146.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/28121871814.pdfIn PDF document text
    • http://senseoftourism.dk/userfiles/file/rogumujatizadoforitakin.pdfIn PDF document text
    • https://www.groupe-coelho.fr/ckfinder/userfiles/files/82025827752.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/q93128fk55s4tjiqjbja6hsrbg/88478868410.pdfIn PDF document text
    • http://hajni.pl/userfiles/file/jurisepebuvifuxufifatew.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/rinipexij.pdfIn PDF document text
    • http://lulanjina.net/upload/files/zumesufogefepex.pdfIn PDF document text
    • http://stark-tools.ru/images/uploaded/37601779869.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/f2rjooouo98oc72ke932ba9058/korurepusi.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/97937237675.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/856b1458e8bebbbc029fe222807c217e/6954035217.pdfIn PDF document text
    • http://sevvalturizm.com/rsm/files/medago.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/36675064472.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/6357706854.pdfIn PDF document text
    • https://www.weldcor.ca/public/ckfinder/userfiles/files/6116705534.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/36815447562.pdfIn PDF document text
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/5f7f903c195708005f91c70d628ea0d6/bixerejajituluduxixogisan.pdfIn PDF document text
    • http://dfwarbitrator.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98853822117.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/16072194b9809a---97939724679.pdfIn PDF document text
    • http://diegogenna.it/userfiles/files/8461956510.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xutosupakep.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/51558243909.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/jdg1qtgg6n5n79o4tm81k4dn07/7409581589.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+do+i+add+apps+to+panasonic+smart+tvPDF 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_off00011040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11040 17908 bytes
SHA-256: 1cd3b5f8ebdadc0e20c7a4faa9f0aba10ccf00ff6adf42160222e1b0cd3b678d
font_01_sfnt_off00013ee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000156f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156F9 10640 bytes
SHA-256: 5d04f28b1889aa3669478220b85ed850979c9d50fe098607114b1ebfc69e0ae3