Malicious PDF — malware analysis report

Static analysis result for SHA-256 7838a1f81de78cb2…

MALICIOUS

PDF

74.4 KB Created: 2021-09-13 03:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 687f3d8eef6259410cec86f75583f554 SHA-1: a81366d778b2473f56c4d884908fd5addb56b06f SHA-256: 7838a1f81de78cb27e9fb93c7413bf0ad4341615e59bdeb062b61e9507819acb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://www.prshots.com/ckfinder/userfiles/files/zomadukenukalimekez.pdf In PDF document text
    • http://plymouth-logs.co.uk/ckfinder/userfiles/files/repugaxujejalawolit.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/dakamopejozesizode.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/15408753475.pdfIn PDF document text
    • http://france-ex.com/images/blog/file/10708677040.pdfIn PDF document text
    • https://tinnituskozpont.hu/files/wujunekopokalurefogo.pdfIn PDF document text
    • http://partnercable.hu/files/letigisojelajipolobiga.pdfIn PDF document text
    • http://an-professional.ru/img/files/file/87578653776.pdfIn PDF document text
    • http://nature-revive.org/files/file/ladunalepexadezuzuwajemi.pdfIn PDF document text
    • https://sanagustin.cl/files/33793785243.pdfIn PDF document text
    • https://gilbertems.com/videos/file/jeligagu.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/hraqai6su3l2uiapr01d73mg5m/89749961646.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/nasifuzaxugekujigalixirod.pdfIn PDF document text
    • https://fortworthdental.net/cmsCart/upload/file/besomubujefifatomim.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/meladitulanowoxuzumidutax.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/ac76d1b70770a04a37b306ce510913ef/nesuvulubinomofokoz.pdfIn PDF document text
    • http://lycee-elm.com/userfiles/file/jorilifa.pdfIn PDF document text
    • http://topbuild.net/content/xuploadimages/file/budilolupuwu.pdfIn PDF document text
    • http://wirheiraten.de/images/file/68046777020.pdfIn PDF document text
    • http://foodchemsino.com/d/files/sepenegolalibufafoxexo.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e709bd3629---66685308574.pdfIn PDF document text
    • http://travelcenterpuntos.com/campannas/file/daluk.pdfIn PDF document text
    • http://fishngrill.iorderfoods.com/uploads/files/fipejizojozu.pdfIn PDF document text
    • https://12shio2.com/contents/files/73336350886.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/91152063370.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/54183873299.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/33668228883.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=pool+party+moto+x3mPDF 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_off0000c116.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC116 16988 bytes
SHA-256: a9c14d3de991651358ab7c16bc0802af9fcfb0b58934755f1291eb3433760c2a
font_01_sfnt_off0000ecee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEE 10304 bytes
SHA-256: e30e4fbdde0ab62975873cc7fa87013341ae886f53f881e6461d13459ae17e51
font_02_sfnt_off00010449.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10449 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1