Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9ab97de3706b49b…

MALICIOUS

PDF

88.3 KB Created: 2021-09-08 10:37:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 925cb2a820bba5e43a54b9b4409e3c7f SHA-1: 5df45cbaa64d48b9478544398b6e160f897a8936 SHA-256: a9ab97de3706b49bbe73aa8c024dc927a931c6ba99bb1d70385f40d62002a7a7
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable domains, suggesting a phishing or malware distribution scheme. The presence of external URI heuristics and link farm indicators further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://tryinvest.eu/userfiles/files/miduwifevumogax.pdf In PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/1nkn2l8mhu1jg7lj3pn2c40q1m/26608739498.pdfIn PDF document text
    • http://sunjewelsonline.com/userfiles/file/tawukanajiros.pdfIn PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/99816521643.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/ed03b249ac3e62de4a9456dd01a8eedf/mububigalutixotiruxuk.pdfIn PDF document text
    • https://expeditions-travel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609191f531a2f---29911688686.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608076576e2de---janasirufirelimoreses.pdfIn PDF document text
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/74a972d280a6c330d905f598b9a183c2/fixulubu.pdfIn PDF document text
    • https://www.hippocratio.gr/ckfinder/userfiles/files/27065797612.pdfIn PDF document text
    • http://100gastro.cz/soubory/files/wibajovevaduvudos.pdfIn PDF document text
    • http://kammed.com/userfiles/file/26865597063.pdfIn PDF document text
    • http://uk-finansist.ru/userfiles/file/44227671962.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdb4031870f---26423386777.pdfIn PDF document text
    • http://wolfroccatiassociati.it/userfiles/files/wezeworikib.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612cbd4077b7c---27654607019.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/e5ace83d51e4d5a6b1f55ecda579e2b5/508988442.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/67c873d9fee5db4138b9e10b7faf772b/butebosaserubunakus.pdfIn PDF document text
    • http://ormansagszive.hu/upload/file/74596486598.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/dfc632e0542feab2fa96d983b72d50b7/99169238783.pdfIn PDF document text
    • https://vanrun-it.nl/userfiles/files/vitukakepa.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c58dac2089e---72255000462.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/duxajogewokupir.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/va0fmui5a0hcrhg83rsnujp9j6/zobenov.pdfIn PDF document text
    • http://beijingbeat.com/contents//files/wuvuruliluwadigavageneko.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/94f5dee6f7fa9a675501e7c6fe926f5c/19609080539.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///63984913499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=short+notes+on+surface+chemistry+class+12+pdfPDF 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_off0000f2d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D5 17504 bytes
SHA-256: ed2799d94ab13effa881b1a25800eed45994bd3e39b5622cb08693a6a31161eb
font_01_sfnt_off00012010.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12010 11348 bytes
SHA-256: 6f5ce5e4508bf03dabce6055611a51b3421c97aceb0f459ad195f12a63005026
font_02_sfnt_off00013ab5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1