Malicious PDF — malware analysis report

Static analysis result for SHA-256 b44676e6b55ba395…

MALICIOUS

PDF

71.5 KB Created: 2021-09-28 13:21:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 64d0190519d17f612159b182da9f4cad SHA-1: bfffa1945181e89eeea70d641500cba6d355b032 SHA-256: b44676e6b55ba3958720d58dd1be9321258485ccbcb0e66d9b6b8ffe739a3062
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and link farm heuristics, suggesting it's designed to redirect users to potentially harmful websites. The presence of embedded URLs and the nature of the heuristics point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://irlanc.ru/uplcv?utm_term=i+forgot+my+mobile+screen+lock+password
    • http://phanphoiongnhuahoasen.vn/upload/files/54943130457.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd70d84309---3979398646.pdf
    • http://harckocsik.hu/userfiles/file/8927682426.pdf
    • http://wonderpanel.com/app/webroot/img/file/94130662097.pdf
    • http://teamtrinity.net/trinitya/file/buxozadokutofu.pdf
    • https://currenwatch.myhost360.cn/file/upload/files/09-19-18-23-43-48.pdf
    • https://perfecthospitals.com/ckfinder/userfiles/files/fimabuvogobutosus.pdf
    • http://dotacjedlaoze.pl/userfiles/file/mujabaretuzeloxexal.pdf
    • https://giasidaily.com/uploads/userfiles/file/89425474842.pdf
    • http://www.agrosystem.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614eb52fc0143---jakeze.pdf
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/tizeragudomutusu.pdf
    • http://talentfuturesservices.com/sharpinstitute/images/files/20598286050.pdf
    • https://lifesmart.ro/ckfinder/userfiles/files/7069213159.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161410f19e9664---xetogolenutujetedojaf.pdf
    • http://lideparts.com/userfiles/file/1630932880.pdf
    • http://bharatandcompany.in/ckfinder/userfiles/files/33965697259.pdf
    • http://cuathepvangohaiduong.com/images/ckeditor/files/kinevobuso.pdf
    • http://nsdadventist.org/FCKData/file/mojimokuxonaman.pdf
    • http://riverla.vn/uploads/userfiles/file/topatemagesikira.pdf
    • http://innotack.com/userfiles/files/tidunomivovubevajijo.pdf
    • http://zaintik.org/files/galeria/files/37904646722.pdf
    • http://exosushi.com/uploads/files/91593777010.pdf
    • http://uptownfallschurch.com/uploads/files/83693322774.pdf
    • https://stonebuild.bg/f/uploads/files/11947657433.pdf
    • http://aallergy.friend-match.com/upload/files/73306026264.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b440.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB440 16792 bytes
font_01_sfnt_off0000cc52.bin
a2255c30895b099bb6a2919e824eeb07dd40352495e4b8e2f8db910b42ced10e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC52 16144 bytes
font_02_sfnt_off0000f5a1.bin
33074c9a450bc00de94a1dfc83f2842c4c0460bbe3f9ccd213da347843dc57cd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A1 11348 bytes