Malicious PDF — malware analysis report

Static analysis result for SHA-256 99752afee9ede985…

MALICIOUS

PDF

86.4 KB Created: 2021-07-02 06:16:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: df8a93f6e3fc19d7cb2ea82b00e664ea SHA-1: 963bb7b159c95f6e7a0474b708d5f61525e8ffdb SHA-256: 99752afee9ede9850becc1c40a99990a2c6fcbde9b4d53aee980812b993749e9
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories. These links likely serve as a distribution mechanism for further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16080b8d19804a---fuwavegewuf.pdf In PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/05d1d966f1df3262aaf36f1f7160fc02/81597805599.pdfIn PDF document text
    • http://dekogard.net/deko/veri/_files/lerexumubafagoreven.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/mowakokesofegitojemadijuj.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160af5cd577eee---nijofotixik.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/m66tck5ouincld7mjhn05is631/90087679800.pdfIn PDF document text
    • http://beergolfers.com./blog/images/file/42357826519.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/50302028886.pdfIn PDF document text
    • http://gloucesterclassof81.com/clients/23558/File/rowopomanemejefuxowutojor.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160c2550f601f4---21830713935.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/5a983814b6ed05b5e249dfac1b0ee586/vibimetojisudufupoju.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/nrq7lf5ug5lv6b0kqc60rrh0q5/wenubimepolinemibivo.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/7862d5d1ea0b48d2eebbf3add7d2077b/6107561422.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/88294296483.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/6sm7e64ahdnl5mquqa4s7cp16n/sukarudapamugojoremexira.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/39cccc5785ce8e70faf2861c7b3a7d7c/wuvan.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/015e8u4g6ke9jb8v9jnnta6to4/modap.pdfIn PDF document text
    • https://tipresentoio.it/images/file/balukukesigefodi.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7b0cc7eaf---tuzaderomelififedavejatim.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/53801b56bbba238525689007475d3e62/rixijokukoliker.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b417d9209---detowudugumaluwewal.pdfIn PDF document text
    • http://at2apigroup3.com/contents//files/50241744158.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609246e320915---59125608492.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b58293134---fobaponir.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/13aba6409c427a366c20c91ce8233b89/98382040276.pdfIn PDF document text
    • https://pensiuneavlasin.ro/wp-content/plugins/super-forms/uploads/php/files/liom3jji7nstodsjmmlfbn7h6q/29615140725.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=50+greatest+harry+potter+moments+2011PDF 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_off0000ec73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010485.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10485 17720 bytes
SHA-256: 6c81cba2ca2f9d39dd252ea995b8d93601efb2d824f747f704d5cd1ade7f4544
font_02_sfnt_off00013246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13246 11008 bytes
SHA-256: 62d88a6efca9a71faf95c1c75b1d4a0fb537a2fde1e360565ec5ed392a336940