Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec428b50da220c10…

MALICIOUS

PDF

80.2 KB Created: 2021-09-17 11:30:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fae2291f04ce569dbe299eba3dbf57e3 SHA-1: 6b692735705be52b348126d6e82dc95224346396 SHA-256: ec428b50da220c10d68c60a333d591c41389970c7b12775480cf3575f99697e4
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs and is flagged by heuristics as a link farm and a potential phishing document. The 'SE_CALLBACK_LURE' heuristic specifically indicates the document prompts the user to call a phone number in a context of billing, refund, or security, which is characteristic of callback phishing or tech-support scams. While no scripts were explicitly extracted, the presence of external URIs and the ML classifier's high confidence suggest malicious intent, likely to redirect users to malicious sites or initiate fraudulent calls.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://coretry.ru/uplcv?utm_term=when+mortal+kombat+movie+2021 PDF link annotation
    • http://csc-021.com/userfiles/file/20210914123535_socghl.pdfIn PDF document text
    • http://holzbau-napetschnig.at/48548940378.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/62373649208.pdfIn PDF document text
    • http://professional-tuner.at/uploaded/file/48397197013.pdfIn PDF document text
    • http://cutskytools.com/d/files/liludofovowota.pdfIn PDF document text
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/xuloguwilimejiriritudi.pdfIn PDF document text
    • http://geredekombiservisi.com/userfiles/file/62632347379.pdfIn PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/ramibixaxepewutetawu.pdfIn PDF document text
    • http://xedaptheduc.net/app/webroot/uploads/files/77258560906.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcc446fe20---23501907405.pdfIn PDF document text
    • http://geodavidepini.it/userfiles/files/lamiguzamemugib.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161435b7a3d00b---28230264808.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/jobexilivase.pdfIn PDF document text
    • http://bitree.net/ckfinder/userfiles/files/wazatadokajesosogu.pdfIn PDF document text
    • https://aordonez.com/images/contenidos/files/40991494951.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/72316544043.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/62337982441.pdfIn PDF document text
    • http://factblogs.com/uploaded_files/userfiles/files/duwejizewasaruwufupex.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/37427874959.pdfIn PDF document text
    • http://tecniagua.es/uploads/ckfinder/files/65919418157.pdfIn PDF document text
    • http://moscowballet.ru/userfiles/file/60166311933.pdfIn PDF document text
    • https://bliznacite.dvsportbg.com/files/vovej.pdfIn PDF document text
    • https://villadelauca.com/userfiles/file/fojokutozodolulirorinobeg.pdfIn PDF document text
    • 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_off0000d1bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1BB 10788 bytes
SHA-256: f5df1cd031cc5955ad1af99acb20e1f37483075eb12fd3d4331b323acd5329c9
font_01_sfnt_off0000ea68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA68 18732 bytes
SHA-256: 48cd0fc326a6592e2e27ab525e162e71c09391497c348fc68fa61a53cbede7c5
font_02_sfnt_off00011b7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1