Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ac984b4f1f3c767…

MALICIOUS

PDF

91.6 KB Created: 2021-07-05 19:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 88c65d7e3d3586acf268832fb1563cb3 SHA-1: 01fff3664e08f452af6eb9715004a52e7c72c80b SHA-256: 3ac984b4f1f3c7671eb32b1b153e69af06c1a054fd42f008b435d51e8a0a6015
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Several URLs point to compromised CMS uploads or disposable hosting, suggesting an attempt to distribute malicious content or phish users. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware delivery attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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
  • 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 http://worldprint.su/userfiles/file/2580924582.pdf In PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/c576b5705c2889caddbcf4a525eddac2/viginutozajewofafunexuk.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/lizomodixuwosifosawi.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/d75636683beee9594feb683ca28f1c66/mumulasobudu.pdfIn PDF document text
    • http://patroha.hu/file/48025921497.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210529171225.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ce1285f9ef---busapopidazawifonizedo.pdfIn PDF document text
    • http://trendybiz.in/usersfiles/file/zurobazasolunawuxorotenap.pdfIn PDF document text
    • https://mimpishio2.net/contents//files/kugojujifote.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/tirovu.pdfIn PDF document text
    • http://mahkotacare.com/tmr/userfiles/files/84511774686.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/mp0da4vket7h2q4jauvfmpi0t6/4842683170.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/surukuvozisuwipitoj.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/44608320770.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/15116336852.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/5776f14066f8602e9381ee88ff2a49c1/zuzopasupaxazedubarafipav.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/cged1gqob3ce0v5eem6n29jtg6/14899283057.pdfIn PDF document text
    • http://jcpingie.be/public/files/tojakunama.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/48619141961.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/97982384202.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/bb40f9a5ec4dce9df495a813d39e4a46/sirapiriwulafigowaxevopi.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/13004326019.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/35167077029.pdfIn PDF document text
    • https://cape-electronics.com/media/file/gunufazot.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/87577612071.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/c0da1b3fe9b97b564096f69f09238e95/58034775213.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=birth+rate+meaningPDF 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_off0001037d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1037D 17784 bytes
SHA-256: f593d1cc3553430c4bced269bcc18cbc8cd6d537531662c360225c50e5fc6f2e
font_01_sfnt_off0001321d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1321D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014a34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A34 10276 bytes
SHA-256: b533732e6f17248247d0c11e00c7fd85206f10ada32b4bc4487fbb567eb09d51