Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a749a6a1e07213…

MALICIOUS

PDF

75.2 KB Created: 2021-09-25 10:11:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: b7fbc2092872d095f163f99bf0234dcc SHA-1: f02a011b74f60d774e84a5dcd33317dad68f34b9 SHA-256: 87a749a6a1e072136d54671018a0b372a7aa77c39c5771150ff9980cd9ad40f2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting, suggesting a link farm used for phishing or malware distribution. The presence of these links and the overall structure align with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/30384c592af98acad98dbd51458fdb42/biwolig.pdf In PDF document text
    • http://baohanhranghm.com/upload/img/files/gafisoremit.pdfIn PDF document text
    • https://fasleh.net/Files/files/balopimevufat.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/buxawalekepobeso.pdfIn PDF document text
    • https://lostfoundglobal.com/userfiles/file/73251772934.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e018d47b59---xikenof.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/xijewemowute.pdfIn PDF document text
    • http://budohurtsa.pl/userfiles/file/kuvurovadupofunapide.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/zezipegojumigevifadiw.pdfIn PDF document text
    • https://www.mnogotrop.com/ckfinder/userfiles/files/29428277003.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/44017617812.pdfIn PDF document text
    • http://www.web-globus.de/ckfinder/userfiles/files/59162779102.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210902125152.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/bulilojekade.pdfIn PDF document text
    • https://frisch.ro/files/file/11355132560.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///36328080864.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/86129027321.pdfIn PDF document text
    • https://locktactyuma.com/userfiles/file/zikomuwuvivapazepexagiw.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/80591192023.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/lui4473eh2cud6543oiflm8uk2/89945176027.pdfIn PDF document text
    • https://seedcambodia.org/htdocs/cljr/data/files/tazebodizu.pdfIn PDF document text
    • http://pes.edu.mn/ckfinder/userfiles/files/vatene.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=cara+mengaktifkan+usb+debugging+android+yang+terkunciPDF 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_off0000bcf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCF8 11252 bytes
SHA-256: 25d3fe5814bdb390eb9b5f019843dd85e79d353a72c61c0cfc09f5b6d78661cc
font_01_sfnt_off0000d731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD731 18328 bytes
SHA-256: 2b72b8fe23ea3379fdb63883f36654a594a18552f85a118638d34d90f2f1dc5d
font_02_sfnt_off000106ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1