Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5a4f73daaf7a950…

MALICIOUS

PDF

80.7 KB Created: 2021-09-21 03:54:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b4fd5c6be79b459a3337a122569fd23b SHA-1: 0349b5c31ec986c02901e06c00d283a61346acb9 SHA-256: e5a4f73daaf7a950e1465edbc0e4b7d8270eaa83cb7119f72f9eede1144fa109
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing lure. It contains a link farm pointing to various PDF files hosted on multiple domains, some of which are associated with compromised CMS uploads. The presence of external URIs and a link farm suggests an attempt to redirect users to download potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://archism.ru/uplcv?utm_term=freedom+apk+direct+download PDF link annotation
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/rugedajajoba.pdfIn PDF document text
    • http://tavio.su/files/file/67676509140.pdfIn PDF document text
    • http://quangcaovuanh.com/vietkiendo/upload/file/wagarupuvenogixuvemov.pdfIn PDF document text
    • http://pastoret.it/userfiles/files/24268312666.pdfIn PDF document text
    • http://jianianhuayule.a9188.com/upload_files/art_files/files/20210903_011504.pdfIn PDF document text
    • http://www.bongbansaigon.com/uploads/files/86370802937.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109071810023494.pdfIn PDF document text
    • https://buddhaart.in/userfiles/file/junaditukinorolofifumuluz.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/71448631584.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140b3a76cbfd---53756232596.pdfIn PDF document text
    • http://maxbrio.kr/files/files/venizifebefodekuvazem.pdfIn PDF document text
    • http://sevoir.hu/uploads/file/53112730323.pdfIn PDF document text
    • https://alariel.be/userfiles/file/87301204566.pdfIn PDF document text
    • http://geoass.eu/userfiles/files/40417596331.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/12189337926.pdfIn PDF document text
    • https://tiemhoahaibara.com/data/dulieu/files/46563856620.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c5c1042068---59435465013.pdfIn PDF document text
    • https://12tiga.com/contents/files/kinixerunedururelemisusi.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/gabojepaxigexam.pdfIn PDF document text
    • http://email-database.info/userfiles/file/fivitujebin.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210919121000.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/b3b3e799eef8d03e2bcc3b1060924b0b/44877824940.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_off0000d53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD53A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4C 18252 bytes
SHA-256: f1cf0427401457467ff3d16a085ed61f3c40fae14faea2cd36cd2acbf056f66b
font_02_sfnt_off00011cd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD1 10660 bytes
SHA-256: dd42b2183a6b0656498b32ef06358bb8b89d61a7e77fc5cb87768b87c56faedd