Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5ff0f78bf797f4e…

MALICIOUS

PDF

79.5 KB Created: 2021-09-15 09:05:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 55cce866ced3852ac794b69b5198dbec SHA-1: e5b182b8c07cc5c896749ada8f0ebb55cbf2f195 SHA-256: a5ff0f78bf797f4e23b2afd786903f8aa287f857c5228599f6e0db64cc6c7634
146 Risk Score

Malware Insights

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

The PDF document was flagged by ClamAV as a phishing trojan and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm on disposable domains, suggesting an attempt to redirect users to malicious sites. The presence of numerous embedded URLs, many pointing to suspicious domains, further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/xafanatolobugiviputukam.pdf In PDF document text
    • https://areopag.ru/sites/default/files/uploads/16286615386.pdfIn PDF document text
    • http://pasted-radio.de/web/files/40628932620.pdfIn PDF document text
    • http://ohsongpharm.com/ckfinder/userfiles/files/punizutane.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/47949935009.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/161400723d4d1c---vadojudonuwobiguse.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/39539571711.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/buvijetesubagewibiwo.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/kawivibarinovum.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/84972058134.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/supazimamatorutofavegax.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/zomemupekowaxokato.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/xekizata.pdfIn PDF document text
    • https://magyar-logyogyasz.hu/fileok/file/80122239441.pdfIn PDF document text
    • http://wpklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pomikemitim.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/raxofu.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/kajolexe.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/kizaroladebifojaxajabapun.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16137a76d857fe---75654883957.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/liponosa.pdfIn PDF document text
    • http://novafish.it/userfiles/files/jukaraz.pdfIn PDF document text
    • https://bompentax.com/quangbasanpham/app/webroot/upload/image/files/natesuvize.pdfIn PDF document text
    • http://anhuizhkj.com/upload_fck/file/2021-9-13/20210913204238682253.pdfIn PDF document text
    • https://y3stwk65l-mn9.com/contents/files/6544436203.pdfIn PDF document text
    • http://sprostredkovanieuverov.sk/res/file/26645085542.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=download+lomotif+app+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_off0000d4fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FB 10444 bytes
SHA-256: 3f2998f5876d7449124b74e1f52b32b133f22fff0aeba02faf22aa0c5e22000b
font_01_sfnt_off0000ec9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104AC 16956 bytes
SHA-256: 6f150ba987be53c70dc5bbfe7e70fc6946175db10a78b4484a6eac4295a4f159