Malicious PDF — malware analysis report

Static analysis result for SHA-256 838cddeeeac074fe…

MALICIOUS

PDF

82.4 KB Created: 2021-09-13 05:05:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 069ace6aa2430826388ad6688c0d1c06 SHA-1: 65615a10cea73e1e862b03931c7bf8ce217d6ff8 SHA-256: 838cddeeeac074fe1bd35cf824c9493f73a5e2ee68d876344fd83a22478e8c0f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing to external websites, many of which are hosted on compromised WordPress installations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The file's structure and numerous outbound links suggest it functions as a link farm to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161302d9aec1ef---dirivuwuravifijopusetibo.pdf In PDF document text
    • https://mandarinkinesiska.com/userfiles/file/fusitolozeduzeliro.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137733266591---lixajosekamawi.pdfIn PDF document text
    • https://sapsda.com/SapmaUserfiles/file/56581389134.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/xavadalowajul.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/71440941351.pdfIn PDF document text
    • http://smingames.com/ckfinder/files/67048675504.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/70707067217.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7a0a1e3a7---4310831313.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/22874346307.pdfIn PDF document text
    • http://needychild.org/ckfinder/userfiles/files/vodelikawozuzugubug.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613525a474f27---lefizejovesat.pdfIn PDF document text
    • https://duvanco.be/docs/files/feronabafozoditat.pdfIn PDF document text
    • http://hodoan.net/userfiles/file/55563647121.pdfIn PDF document text
    • http://alkanboya.com/files/file///39661349381.pdfIn PDF document text
    • http://cityclick.it/userfiles/files/dinulabasigubamuwasipi.pdfIn PDF document text
    • http://gibisch.info/files/files/wabavasogumubonolixi.pdfIn PDF document text
    • https://pakianco.ir/data/image/uploads/news/files/taxisotimufibun.pdfIn PDF document text
    • https://snf.styleguides.ch/userfiles/files/63249233390.pdfIn PDF document text
    • http://hertzlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xujoromuvarixuz.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/lisenexeriluderujub.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfb8c00eb6---95664669958.pdfIn PDF document text
    • http://ghalemdi.com/userfiles/file/sepekidunetilokazo.pdfIn PDF document text
    • https://dbhattacharjee.com/ckfinder/userfiles/files/tudukudubejudofotivovukup.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/33135658181.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=mini+pc+for+android+4PDF 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_off0000df1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1E 17872 bytes
SHA-256: b7b243d7e1d27541eb010fe4820315e17acbb1d21bf6c728ab00d46224fb6b96
font_01_sfnt_off00010d42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012559.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12559 10240 bytes
SHA-256: 40021d4b62a8f244a9b97b405d2306a5b3d3b520d747408db88332c34ffc8090