Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1bb99f5aaffa1aa…

MALICIOUS

PDF

88.2 KB Created: 2021-06-29 14:31:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 738d2af53feb09ba6c1756ad4305efea SHA-1: 235be4a09bdc7e34f711da9523a0448dd0cfa2e8 SHA-256: d1bb99f5aaffa1aa7ad19b447a0a3b12bbeac7aea4a92fc8378c6a37a4bdf23c
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The PDF structure and embedded links point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://cornucopiafrederick.com/uploads/files/31363947364.pdf In PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/li1348juu9h428d9l2gno6qka5/85206639635.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/9d178acc7f61c825eefb93be9ed573c6/74420790426.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/76655354800.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/kotap.pdfIn PDF document text
    • http://snsi.jp/image/news_file/89278423296.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa081470108---zuzuzus.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea366af901---ximofow.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/8011bc08b280622a5ad9fd020cb9d346/86819210629.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/zitedatuvukiliwi.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/c4c5ad1fbce1a9c11e64c6e485da2196/kijepivirabunuwewiteliju.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/34515985931.pdfIn PDF document text
    • https://makenie.com/upload/files/fagapikogozezi.pdfIn PDF document text
    • https://bem-sa.com/img/file/jijotelozifus.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16070157b294f7---mobezujomobizalaguguxivi.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7a92d513a---7130693320.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///52991239490.pdfIn PDF document text
    • http://universalestetic.com/userfiles/file/41239946838.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/15cbea03f20b16516830859958762a84/11020255045.pdfIn PDF document text
    • http://peak-experience-japan.com/68321932323.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/75076488541.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/0c4365f234044e77ef10074ffd08a11a/wuzebapigamixap.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/ngpftr89niri2ocaa30ccdssm5/85972991320.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1d0a63b25---5000159983.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2201c81d8---99258816343.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=surface+area+of+trapezoidal+prism+worksheetPDF 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_off0000f453.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF453 17008 bytes
SHA-256: 6d70831b9a1a1494cb95e3bb1c1827431d8418d98ba4ae9884103185bdaccbd2
font_01_sfnt_off000120d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D7 11192 bytes
SHA-256: 669138138a9c78cdb67bbd4524489a26c832008408b65879b9237db2b58dbb6b
font_02_sfnt_off00013b24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1