Malicious PDF — malware analysis report

Static analysis result for SHA-256 4de81a52a5402ab1…

MALICIOUS

PDF

92.0 KB Created: 2021-09-17 07:57:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5d8eb9dcca878d62916b0101a95b5b3d SHA-1: c1e68b519cd7b5d4332edf58db61fa853bf1591f SHA-256: 4de81a52a5402ab10086ac8ad2454959e93d3aae7109db62ecc036f69a210e90
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The presence of numerous links, including those with 'utm_term' parameters, suggests an attempt to drive traffic to potentially malicious or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://oniceh.ru/uplcv?utm_term=connect+my+phone+to+mi+tv PDF link annotation
    • https://oklogistic.lv/upload/file/wetusufosuge.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/43d2368fd48abfe50a52c80964e32e8d/mofasazeviwigazefowuk.pdfIn PDF document text
    • http://insightonafrica.in/userfiles/file/jovigorimunemepalakukezes.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/zusofemelonetem.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1613748fc91e58---94333168605.pdfIn PDF document text
    • https://propertiproperty.com/Uploads/userfiles/files/85269990615.pdfIn PDF document text
    • https://073741256.com/uploads/files/202109110657063002.pdfIn PDF document text
    • https://oancora.com/ckfinder/files/dowosol.pdfIn PDF document text
    • http://musorcentrum.around.hu/files/article/file/44043010529.pdfIn PDF document text
    • http://strandedtattoo.net/file/35291484358.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/grmp8a55ctkbrop4c8j7l3irhr/tolonagegoli.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e481255acc---kixovakosota.pdfIn PDF document text
    • https://buddhaart.in/userfiles/file/jimuka.pdfIn PDF document text
    • http://isuzuphonoi.com/data/dulieu/files/lakomosaxoku.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021091413092473499.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202109130208525916.pdfIn PDF document text
    • https://doitoutdoorz.com/file/RcgLVPFqygpRc6fx.pdfIn PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/rupavirezo.pdfIn PDF document text
    • http://mgtofubbq.com/uploads/files/93282460774.pdfIn PDF document text
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613994aad692c---nasugevobetapedide.pdfIn PDF document text
    • https://guineaservicesproviders.com/gsp/files/sibiwebejakibofu.pdfIn PDF document text
    • http://ghettaetamionarchitetti.it/userfiles/files/42178148789.pdfIn PDF document text
    • 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_off00010273.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10273 10376 bytes
SHA-256: 8b443090294b2366971d5273f35df9440a862f1f89b308ad9787140c6e42aeea
font_01_sfnt_off000119c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131D2 18736 bytes
SHA-256: 492cdae4f197da9254ed5f2077dc12c0e94ee8e9b14ba9a762bac51c8331ecca