Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5335e3154dda3b6…

MALICIOUS

PDF

86.5 KB Created: 2021-07-05 17:55:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 693b3d6ba146913c9578cf9890d7e14a SHA-1: 57bcd83f72e955ae0aa1f50e1c8bcc7a3bc7e593 SHA-256: b5335e3154dda3b6729a65d03d8aa15881acbff73f019b91fcf9ffab73329445
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised WordPress sites and disposable hosting, designed to redirect users to various external URLs. The presence of multiple unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://n95america.com/wp-content/plugins/super-forms/uploads/php/files/ef6a81607c1029512cea07b957be043c/45138094329.pdf In PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a45365b3fb8---86711610020.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/wuvepunire.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b83fb3fa28---93141177093.pdfIn PDF document text
    • https://landi-bg.com/images/file/sajixuxidojurekijeto.pdfIn PDF document text
    • http://biosurfest.com/userfiles/files/besufifepud.pdfIn PDF document text
    • http://barcabianca.eu/upload/file/kifuvukixixegiw.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/wosiluniripafemelaf.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/2da6d0f9fe08ff103d81c180932b75d3/vivurejowisutonixidode.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b591d568640---57117490854.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/retenojewujubenexoxapaf.pdfIn PDF document text
    • http://ergo-logo-bamberg.de/userfiles/file/lemuloneruris.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/fojidukuk.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/qp7s3v3ni5us7qlqn6hkivf5e4/sunepupewerus.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/xabivunamogubeweb.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160873868e7369---10213822364.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/ca79a3a4c688f0a7cd632bb4492141d0/76016084284.pdfIn PDF document text
    • http://saxonsaxtonfamilyreunion.com/clients/f/f6/f6d0431f970e0833b0867c311dafb132/File/14820717586.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/16068414058.pdfIn PDF document text
    • http://andreaslasnik.com/data/files/71176895500.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079fd8048cfb---93589054732.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160831623a57e0---tokiwovotoxakefe.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/u5h66osbr36no4smsgspi213cp/57069655858.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/82838436818.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=heartless+by+the+weekndPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000116ee.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x116EE 17916 bytes
SHA-256: e2729ff6eb6e3ebfc258f0c4fcbb59929cf8fffbb115289060c6f7e9c7a5f6d9
font_00_sfnt_off0000c1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA0B 24596 bytes
SHA-256: 49e9cd1dc61b89411bfc4adc1b1d5cb3f12d15e5a1ee9a5f854445de981cb90f
font_03_sfnt_off000132c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132C8 10556 bytes
SHA-256: f7458da7ed2912e07d0fe4334daf3938b4fe03f5395dec4e73bc42fb1369e1b5