Malicious PDF — malware analysis report

Static analysis result for SHA-256 4670622f975a9b11…

MALICIOUS

PDF

77.8 KB Created: 2021-09-17 06:22:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f8cf3a1ab5d19a7e77a7db43ae069ef0 SHA-1: 48b291ca8e679113c2583409a4b9536f24dda598 SHA-256: 4670622f975a9b11196627b0e1bec8f93dd20dd83ef2a8e59fc0ef259ed4637d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many hosted on compromised websites or disposable domains, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect the user to malicious content, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://smidgel.ru/uplcv?utm_term=cnc+simulator+apk+full PDF link annotation
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/98606197102.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613bdb29794ce---zexalagesova.pdfIn PDF document text
    • http://myepres.com/HotelEstimator/userfiles/file/42820672613.pdfIn PDF document text
    • http://synhbio.com/upload/files/73673300823.pdfIn PDF document text
    • https://ddriu.hu/wp-content/plugins/super-forms/uploads/php/files/405871395af83ed3baeffb29fa4ca9d3/56918253829.pdfIn PDF document text
    • http://lesen-und-schenken.de/userfiles/files/28112270680.pdfIn PDF document text
    • https://sjamsul-hidajat.id/ck_uploads/uploads/files/45222824350.pdfIn PDF document text
    • https://atavio.ru/files/file/pebixa.pdfIn PDF document text
    • https://xn--psg-9lac.hu/files/files/97204719268.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/tobodo.pdfIn PDF document text
    • http://garderoba.sk/images/_file/92495178889.pdfIn PDF document text
    • https://bushregenerators.info/userfiles/files/xowufubome.pdfIn PDF document text
    • https://windfreeklima.com/upload/ckfinder/files/wofelunekogukew.pdfIn PDF document text
    • http://cainghienbinhduong.com/uploads/userfiles/file/88795574090.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/81469432491.pdfIn PDF document text
    • https://egf.tw/test2/images/file/55266006380.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/48e36c01d166da5d42c2f3221bb26372/53865930258.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/98623588370.pdfIn PDF document text
    • http://khautrangkhangviet.com/upload/img/files/11213881970.pdfIn PDF document text
    • http://interstroy96.ru/uploads/files/mafuridotema.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/tadolugupejuv.pdfIn PDF document text
    • https://agape4u.org/userfiles/file/tupototidosi.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/65966426820.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_off0000ca4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA4B 17828 bytes
SHA-256: 7342f5df6cb0189c1dd566e614d44ecdb91ba694c69f9b89cf1eb81d2014837f
font_01_sfnt_off0000f8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8F6 10732 bytes
SHA-256: 7983ebd222bb1bd89578708b028cdbc3ec3e48d754fee8e53c65e89f942ed37c
font_02_sfnt_off000111ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1