Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a07540856115d9…

MALICIOUS

PDF

85.0 KB Created: 2021-09-12 23:52:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 608aa2de9b9b8270886a5b477518c5f2 SHA-1: 82feb55aaf39c075c14c0ad5464afb565a72e3d6 SHA-256: 87a07540856115d92ffaecf249c3c5d8e1d62c7003aa4881548d25c880585a03
164 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ML classifier 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 hosting, suggesting an attempt to redirect users to malicious content or for SEO spam. The presence of external URI heuristics and link farm indicators supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://erago.cidees.com/uploads/files/kejukatave.pdf In PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/dovanojixapawi.pdfIn PDF document text
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/161387c347b89e---76420483989.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/59229631829.pdfIn PDF document text
    • https://gloriamus.org/Uploads/userfiles/files/73670435987.pdfIn PDF document text
    • https://banktapeunadana.com/tapeunadana/bank2/admin/userfiles/file/varatuveriwa.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/35923776575.pdfIn PDF document text
    • http://www.xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/gexararipifibufaromajag.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3b52c0762---71320254973.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-11/20210911212627313219.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/d8a8652e4cf833b6304be2b97c35abf7/20283886805.pdfIn PDF document text
    • https://textolinguisticsolutions.com/upload/editor/file/zefigite.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135ee86c078a---gufeteselopepozusetatodi.pdfIn PDF document text
    • http://fcvperu.org/data/fcvperu/userfiles/file/63013708570.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/fajavonododozafuroxigon.pdfIn PDF document text
    • http://geasit.it/userfiles/files/jewirududoduvomewapelavi.pdfIn PDF document text
    • http://knshzj.com/CKEdit/upload/files/90135076564.pdfIn PDF document text
    • http://capri.lt/userfiles/files/57498654436.pdfIn PDF document text
    • https://soudurelauziere.ca/upload/editor/file/40586540761.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ca91dc9b54---84893717708.pdfIn PDF document text
    • https://motecx.com/images/file/wefumemopepoboxe.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161357b1ce3c1f---vezofu.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/mewixirureraxexagedi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=best+adult+porn+games+for+androidPDF 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_off0000e6db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF2 10996 bytes
SHA-256: fa7aedac4d49928ebd979d71e656e5485fe0a29456e72d513a796e3d596273b0
font_02_sfnt_off00011842.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11842 17640 bytes
SHA-256: 3330695548cc3292852476427f1b20b3a2e205a64d4f961ba45e2861b6966571